97909_Ans_Ans_pA065-075.qk_97909_Ans_Ans_pA065-A075 10/7/10 2:30 PM Page 65 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I Answers to Odd-Numbered Exercises I 35. 共⫺⬁, 0兲 傼 共5, ⬁兲 CHAPTER 1 EXERCISES 1.1 N 37. 关0, 4兴 39. 共⫺⬁, ⬁兲 PAGE 19 41. 共⫺⬁, ⬁兲 y 1. Yes 3. (a) 3 y 2 (b) ⫺0.2 (c) 0, 3 (d) ⫺0.8 (e) 关⫺2, 4兴, 关⫺1, 3兴 (f) 关⫺2, 1兴 5. 关⫺85, 115兴 7. No 9. Yes, 关⫺3, 2兴, 关⫺3, ⫺2兲 傼 关⫺1, 3兴 11. Diet, exercise, or illness 13. A65 5 0 x 1 0 _2 _1 t T 43. 关5, ⬁兲 45. 共⫺⬁, 0兲 傼 共0, ⬁兲 y y 4 t 0 15. (a) 500 MW; 730 MW 17. T midnight 19. 2 (b) 4 AM; noon 0 0 47. 共⫺⬁, ⬁兲 t noon 49. 共⫺⬁, ⬁兲 y amount y (0, 2) (0, 1) _2 0 21. 23. (a) 0 Wed. Wed. ⫺1 5 再 11 2 ,1艋x艋5 0 53. f 共x兲 苷 1 ⫺ s⫺x ⫺x ⫹ 3 if 0 艋 x 艋 3 2 x ⫺ 6 if 3 ⬍ x 艋 5 57. A共L兲 苷 10L ⫺ L2, 0 ⬍ L ⬍ 10 59. A共x兲 苷 s3 x 2兾4, x ⬎ 0 61. S共x兲 苷 x 2 ⫹ 共8兾x兲, x ⬎ 0 3 2 63. V共x兲 苷 4x ⫺ 64x ⫹ 240x, 0 ⬍ x ⬍ 6 55. f 共x兲 苷 Wed. 1 x 1 51. f 共x兲 苷 2 x ⫺ price height of grass Wed. x x 5 Wed. t N 再 65. F共x兲 苷 200 15共40 ⫺ x兲 if 0 艋 x ⬍ 40 0 if 40 艋 x 艋 65 15共x ⫺ 65兲 if x ⬎ 65 F 600 150 (100, 525) 100 50 1996 2000 2004 t (midyear) (b) 126 million; 207 million 25. 12, 16, 3a 2 ⫺ a ⫹ 2, 3a 2 ⫹ a ⫹ 2, 3a 2 ⫹ 5a ⫹ 4, 6a 2 ⫺ 2a ⫹ 4, 12a 2 ⫺ 2a ⫹ 2, 3a 4 ⫺ a 2 ⫹ 2, 9a 4 ⫺ 6a 3 ⫹ 13a 2 ⫺ 4a ⫹ 4, 3a 2 ⫹ 6ah ⫹ 3h 2 ⫺ a ⫺ h ⫹ 2 27. ⫺3 ⫺ h 29. ⫺1兾共ax兲 31. 共⫺⬁, ⫺3兲 傼 共⫺3, 3兲 傼 共3, ⬁兲 33. 共⫺⬁, ⬁兲 0 67. (a) 40 65 100 x (b) $400, $1900 R (%) 15 10 0 10,000 20,000 I (in dollars) Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. x 97909_Ans_Ans_pA065-075.qk_97909_Ans_Ans_pA065-A075 10/7/10 2:30 PM Page 66 A66 (c) APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES 15. (a) T 苷 6 N ⫹ (b) 6 , change in ⬚F for every chirp per minute change (c) 76⬚F 17. (a) P 苷 0.434d ⫹ 15 (b) 196 ft 19. (a) Cosine (b) Linear 21. (a) 15 Linear model is appropriate. 1 T (in dollars) 2500 1000 0 10,000 20,000 30,000 I (in dollars) 307 6 1 69. f is odd, t is even 71. (a) 共⫺5, 3兲 (b) 共⫺5, ⫺3兲 73. Odd 75. Neither 77. Even 79. Even; odd; neither (unless f 苷 0 or t 苷 0) 61,000 0 EXERCISES 1.2 N PAGE 33 1. (a) Logarithmic (b) Root (c) Rational (d) Polynomial, degree 2 (e) Exponential (f) Trigonometric 3. (a) h (b) f (c) t 5. (a) y 苷 2x ⫹ b, y b=3 b=0 b=_1 where b is the y-intercept. (b) y 苷 ⫺0.000105x ⫹ 14.521 (c) y 苷 ⫺0.00009979x ⫹ 13.951 15 (b) (c) 61,000 0 (d) About 11.5 per 100 population y=2x+b 23. (a) x 6.0 (e) About 6% (f) No Linear model is appropriate. height (m) 5.5 5.0 (b) y 苷 mx ⫹ 1 ⫺ 2m, where m is the slope. (c) y 苷 2x ⫺ 3 4.5 y m=1 4.0 m=_1 3.5 m=0 (2, 1) 1896 x 1920 1940 1960 1980 2000 year (b) y 苷 0.0265x ⫺ 46.8759 (c) 6.27 m; higher 25. Four times as bright 27. (a) N 苷 3.1046 A0.308 (b) 18 y-1=m(x-2) 7. Their graphs have slope ⫺1. 1900 y (d) No c=_1 EXERCISES 1.3 c=_2 0 x c=2 c=1 c=0 9. f 共x兲 苷 ⫺3x共x ⫹ 1兲共x ⫺ 2兲 11. (a) 8.34, change in mg for every 1 year change (b) 95 , change in ⬚F for every 1⬚C change; 32, Fahrenheit temperature corresponding to 0⬚C (100, 212) F= 95 C+32 32 (_40, _40) (b) y 0 (c) y 1 1 (b) 8.34 mg F PAGE 42 1. (a) y 苷 f 共x兲 ⫹ 3 (b) y 苷 f 共x兲 ⫺ 3 (c) y 苷 f 共x ⫺ 3兲 (d) y 苷 f 共x ⫹ 3兲 (e) y 苷 ⫺f 共x兲 (f) y 苷 f 共⫺x兲 (g) y 苷 3f 共x兲 (h) y 苷 13 f 共x兲 3. (a) 3 (b) 1 (c) 4 (d) 5 (e) 2 5. (a) 13. (a) N 0 x 1 (d) y 1 0 2 x y 1 1 x 0 1 x C 7. y 苷 ⫺s⫺x 2 ⫺ 5x ⫺ 4 ⫺ 1 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA065-075.qk_97909_Ans_Ans_pA065-A075 10/7/10 2:30 PM Page 67 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 9. 11. y x=_2 y y=_ Œ„x 1 y= x+2 0 0 x x 33. (a) 共 f ⴰ t兲共x兲 苷 1 ⫺ 3 cos x, 共⫺⬁, ⬁兲 (b) 共t ⴰ f 兲共x兲 苷 cos 共1 ⫺ 3x兲, 共⫺⬁, ⬁兲 (c) 共 f ⴰ f 兲共x兲 苷 9x ⫺ 2, 共⫺⬁, ⬁兲 (d) 共t ⴰ t兲共x兲 苷 cos 共cos x兲, 共⫺⬁, ⬁兲 2x 2 ⫹ 6x ⫹ 5 , 兵 x x 苷 ⫺2, ⫺1其 共x ⫹ 2兲共x ⫹ 1兲 x2 ⫹ x ⫹ 1 (b) 共t ⴰ f 兲共x兲 苷 , {x x 苷 ⫺1, 0其 共x ⫹ 1兲2 x 4 ⫹ 3x 2 ⫹ 1 (c) 共 f ⴰ f 兲共x兲 苷 , {x x 苷 0其 x共x 2 ⫹ 1兲 2x ⫹ 3 , {x x 苷 ⫺2, ⫺ 53 } (d) 共t ⴰ t兲共x兲 苷 3x ⫹ 5 ⱍ 35. (a) 共 f ⴰ t兲共x兲 苷 13. 15. y ⱍ y y=sin(x/2) x-2-1 y=œ„„„„ 0 1 ⱍ 2π x 0 x 3 ⱍ (2, _1) 17. 37. 共 f ⴰ t ⴰ h兲共x兲 苷 3 sin共x 兲 ⫺ 2 2 39. 共 f ⴰ t ⴰ h兲共x兲 苷 sx 6 ⫹ 4x 3 ⫹ 1 41. t共x兲 苷 2x ⫹ x 2, f 共x兲 苷 x 4 y 1 π 0 19. y=21 (1-cos x) 21. y y=_(x+1)@+2 2 3 43. t共x兲 苷 s x , f 共x兲 苷 x兾共1 ⫹ x兲 x 45. t共t兲 苷 t 2, f 共t兲 苷 sec t tan t 47. h共x兲 苷 sx , t共x兲 苷 x ⫺ 1, f 共x兲 苷 sx y 2 49. h共x兲 苷 sx, t共x兲 苷 sec x, f 共x兲 苷 x 4 y=|x - 2| 51. (a) 4 (b) 3 in the domain of t. 1 x _1 0 2 x y 1 (c) 0 (e) 4 (d) Does not exist; f 共6兲 苷 6 is not (f) ⫺2 (b) 共A ⴰ r兲共t兲 苷 3600 t 2; the area of the circle as a function of time 55. (a) s 苷 sd 2 ⫹ 36 (b) d 苷 30t (c) 共 f ⴰ t兲共t兲 苷 s900t 2 ⫹ 36; the distance between the lighthouse and the ship as a function of the time elapsed since noon 53. (a) r共t兲 苷 60t 0 23. 57. (a) y=| œ„ x-1 | (b) H 1 0 1 0 冋 V 120 x t 0 V共t兲 苷 120H共t兲 册 2 共t ⫺ 80兲 25. L共t兲 苷 12 ⫹ 2 sin 365 27. (a) The portion of the graph of y 苷 f 共x兲 to the right of the y-axis is reflected about the y-axis. (b) (c) y A67 (c) V 240 V共t兲 苷 240H共t ⫺ 5兲 0 t 5 y y= sin |x| 59. Yes; m1 m 2 61. (a) f (x兲 苷 x 2 ⫹ 6 63. Yes y=œ„„ |x| 0 x 0 29. (a) 共 f ⫹ t兲共x兲 苷 x ⫹ 5x ⫺ 1, 共⫺⬁, ⬁兲 (b) 共 f ⫺ t兲共x兲 苷 x 3 ⫺ x 2 ⫹ 1, 共⫺⬁, ⬁兲 (c) 共 ft兲共x兲 苷 3x 5 ⫹ 6x 4 ⫺ x 3 ⫺ 2x 2, 共⫺⬁, ⬁兲 x 3 ⫹ 2x 2 (d) 共 f兾t兲共x兲 苷 , {x x 苷 ⫾1兾s3 } 3x 2 ⫺ 1 3 2 ⱍ (b) t共x兲 苷 x 2 ⫹ x ⫺ 1 x EXERCISES 1.4 N PAGE 50 1. (c) 3. 100 _10 40 31. (a) 共 f ⴰ t兲共x兲 苷 4x ⫹ 4x, 共⫺⬁, ⬁兲 2 (b) 共t ⴰ f 兲共x兲 苷 2x 2 ⫺ 1, 共⫺⬁, ⬁兲 (c) 共 f ⴰ f 兲共x兲 苷 x 4 ⫺ 2x 2, 共⫺⬁, ⬁兲 (d) 共t ⴰ t兲共x兲 苷 4x ⫹ 3, 共⫺⬁, ⬁兲 _300 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. t 97909_Ans_Ans_pA065-075.qk_97909_Ans_Ans_pA065-A075 10/7/10 2:30 PM Page 68 A68 5. ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 7. 8 31. 3500 _2.5 _20 _50 260 11. 1.1 _4 1.5 0 _0.01 0.01 0 13. 2.5 20 _3500 0 9. 100 _1.5 11 If c ⬍ ⫺1.5, the graph has three humps: two minimum points and a maximum point. These humps get flatter as c increases until at c 苷 ⫺1.5 two of the humps disappear and there is only one minimum point. This single hump then moves to the right and approaches the origin as c increases. 33. The hump gets larger and moves to the right. 35. If c ⬍ 0, the loop is to the right of the origin; if c ⬎ 0, the loop is to the left. The closer c is to 0, the larger the loop. 2 EXERCISES 1.5 _2π _ 2π π 25 π 25 _11 _2 15. (b) Yes; two are needed 17. 2 -1 -2 -3 1 _1.5 1 (c) 共0, ⬁兲 (d) See Figures 4(c), 4(b), and 4(a), respectively. 7. All approach 0 as x l ⫺⬁, 5 y=20 ® y=5® y=´ all pass through 共0, 1兲, and y=2® all are increasing. The larger the base, the faster the rate of increase. 9. 1 PAGE 57 1. (a) 4 (b) x ⫺4兾3 12 3. (a) 16b (b) 648y 7 5. (a) f 共x兲 苷 a x, a ⬎ 0 (b) ⺢ _1 _1 N 2 0 The functions with base greater than 1 are increasing and those with base less than 1 are decreasing. The latter are reflections of the former about the y-axis. 1 ® y=” 13 ’® y=” 10 ’ 5 y=10® y=3® _1 19. No 21. ⫺0.72, 1.22 27. ⫺0.31 ⬍ x ⬍ 0.31 29. (a) 23. 0.65 25. t _2 (b) 3 11. 2 x x %œ„ _3 ^œx„ y y=10 3 0 _1 x+2 x y=_2–® 4 _1 _1 1 _2 _2 (c) 13. y Œ„ x $œx„ x œ„ 2 0 _1 0 x 2 x Œ„ œ„ x $œx„ 15. y y=1 1 x %œ„ ”0, 2 ’ 3 _1 0 1 y=1- 2 e–® _1 (d) Graphs of even roots are similar to sx, graphs of odd roots are 3 n similar to s x. As n increases, the graph of y 苷 s x becomes steeper near 0 and flatter for x ⬎ 1. x 17. (a) y 苷 e x ⫺ 2 ⫺x (d) y 苷 e (b) y 苷 e x⫺2 (e) y 苷 ⫺e⫺x (c) y 苷 ⫺e x Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA065-075.qk_97909_Ans_Ans_pA065-A075 10/7/10 2:30 PM Page 69 APPENDIX I 19. (a) 共⫺⬁, ⫺1兲 傼 共⫺1, 1兲 傼 共1, ⬁兲 (b) 共⫺⬁, ⬁兲 21. f 共x兲 苷 3 ⴢ 2 x 27. At x ⬇ 35.8 29. (a) 3200 (b) 100 ⴢ 2 t兾3 (c) 10,159 (d) ANSWERS TO ODD-NUMBERED EXERCISES 49. (a) 共0, ⬁兲; 共⫺⬁, ⬁兲 (c) y A69 (b) e ⫺2 x=0 t ⬇ 26.9 h 60,000 ƒ=ln x+2 0 40 0 31. P 苷 2614.086共1.01693兲t; 5381 million; 8466 million EXERCISES 1.6 N PAGE 69 1. (a) See Definition 1. (b) It must pass the Horizontal Line Test. 3. No 5. No 7. Yes 9. No 11. Yes 13. No 15. (a) 6 (b) 3 17. 0 9 19. F 苷 5 C ⫹ 32; the Fahrenheit temperature as a function of the Celsius temperature; 关⫺273.15, ⬁兲 1 2 21. y 苷 3 共x ⫺ 1兲 2 ⫺ 3, x 艌 1 1 23. y 苷 2 共1 ⫹ ln x兲 25. y 苷 e x ⫺ 3 ⫺1 4 27. f 共x兲 苷 sx ⫺ 1 29. 6 y f f –! f x 0 f –! 6 0 51. 53. 55. 57. 59. (a) (a) (a) (a) x e–@ 共7 ⫺ ln 6兲 (b) 13 共e 2 ⫹ 10兲 5 ⫹ log 2 3 or 5 ⫹ 共ln 3兲兾ln 2 (b) 12 (1 ⫹ s1 ⫹ 4e ) 0⬍x⬍1 (b) x ⬎ ln 5 共ln 3, ⬁兲 (b) f ⫺1共x兲 苷 ln共e x ⫹ 3兲; ⺢ 1 4 5 The graph passes the Horizontal Line Test. 4 _2 _1 3 3 3 3 f ⫺1(x) 苷 ⫺ 16 s 4 (s D ⫺ 27x 2 ⫹ 20 ⫺ s D ⫹ 27x 2 ⫺ 20 ⫹ s 2 ), where D 苷 3 s3 s27x 4 ⫺ 40x 2 ⫹ 16; two of the expressions are complex. 61. (a) f ⫺1共n兲 苷 共3兾ln 2兲 ln共n兾100兲; the time elapsed when there are n bacteria (b) After about 26.9 hours 63. (a) 兾3 (b) 65. (a) 兾4 (b) 兾4 67. (a) 10 (b) 兾3 71. x兾s1 ⫹ x 2 73. π 2 y=sin– ! x 31. (a) f ⫺1 共x兲 苷 s1 ⫺ x 2 , 0 艋 x 艋 1; f ⫺1 and f are the same function. (b) Quarter-circle in the first quadrant 33. (a) It’s defined as the inverse of the exponential function with base a, that is, log a x 苷 y &? a y 苷 x. (b) 共0, ⬁兲 (c) ⺢ (d) See Figure 11. 35. (a) 3 (b) ⫺3 37. (a) 3 (b) ⫺2 39. ln 1215 41. ln 43. sx x⫹1 π _2 π 2 The second graph is the reflection of the first graph about the line y 苷 x. π _2 y=log 1.5 x 3 y=ln x y=log 10 x 0 4 y=log 50 x All graphs approach ⫺⬁ as x l 0⫹, all pass through 共1, 0兲, and all are increasing. The larger the base, the slower the rate of increase. 45. About 1,084,588 mi 47. (a) (b) y 2 0 y=-ln x x 0 (b) 关⫺兾2, 兾2兴 (b) h⫺1共x兲 苷 共1兾c兲 f ⫺1共x兲 77. (a) t⫺1 共x兲 苷 f ⫺1共x兲 ⫺ c CHAPTER 1 REVIEW N PAGE 72 True-False Quiz 3. False 13. False 5. True 7. False 9. True Exercises y y=log 10 (x+5) _4 75. (a) 关⫺3, 0兴 1. False 11. False ⫺5 _5 y=sin x 1 x 1. (a) 2.7 (b) 2.3, 5.6 (c) 关⫺6, 6兴 (d) 关⫺4, 4兴 (e) 关⫺4, 4兴 (f) No; it fails the Horizontal Line Test. (g) Odd; its graph is symmetric about the origin. 1 1 3. 2a ⫹ h ⫺ 2 5. ( ⫺⬁, 3 ) 傼 ( 3 , ⬁), 共⫺⬁, 0兲 傼 共0, ⬁兲 7. 共⫺6, ⬁兲, ⺢ Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA065-075.qk_97909_Ans_Ans_pA065-A075 10/14/10 5:02 PM Page 70 A70 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 9. (a) Shift the graph 8 units upward. (b) Shift the graph 8 units to the left. (c) Stretch the graph vertically by a factor of 2, then shift it 1 unit upward. (d) Shift the graph 2 units to the right and 2 units downward. (e) Reflect the graph about the x-axis. (f) Reflect the graph about the line y 苷 x (assuming f is one-to-one). 11. 13. y 9. (a) _1 ƒ=max{x, 1/x} y (b) y 1 x π x 1 y=_sin 2x 0 y ƒ=max{sin x, cos x} 1 y= 2 (1+´) _3π 4 1 1 y= 2 0 5π 4 0 _7π 4 x π 4 x _œ„2/2 15. y 1 x=_2 y= x+2 1 2 (c) 0 y x 4 (b) Odd (c) Even (d) Neither 17. (a) Neither 19. (a) 共 f ⴰ t兲共x兲 苷 ln共x 2 ⫺ 9兲, 共⫺⬁, ⫺3兲 傼 共3, ⬁兲 (b) 共t ⴰ f 兲共x兲 苷 共ln x兲 ⫺ 9, 共0, ⬁兲 (c) 共 f ⴰ f 兲共x兲 苷 ln ln x, 共1, ⬁兲 (d) 共t ⴰ t兲共x兲 苷 共x 2 ⫺ 9兲2 ⫺ 9, 共⫺⬁, ⬁兲 21. y 苷 0.2493x ⫺ 423.4818; about 77.6 years 23. 1 25. (a) 9 (b) 2 (c) 1兾s3 (d) ƒ=max{≈, 2+x, 2-x} 2 27. (a) _2 3 5 11. 5 ⬇ 4.4 years 1000 0 2 x 13. x 僆 [⫺1, 1 ⫺ s3 ) 傼 (1 ⫹ s3, 3] 19. fn共x兲 苷 x 2 15. 40 mi兾h n⫹1 CHAPTER 2 EXERCISES 2.1 10 0 冉 冊 1000 ⫺ P ; the time required for the population 9P to reach a given number P. (c) ln 81 ⬇ 4.4 years (b) t 苷 ⫺ln PRINCIPLES OF PROBLEM SOLVING N PAGE 80 a 苷 4 sh ⫺ 16兾h, where a is the length of the altitude and h is the length of the hypotenuse 7 3. ⫺ 3 , 9 2 1. 5. 7. y y 1 x x PAGE 86 1. (a) ⫺44.4 , ⫺38.8 , ⫺27.8 , ⫺22.2 , ⫺16.6 (b) ⫺33.3 (c) ⫺33 13 3. (a)(i) 2 (ii) 1.111111 (iii) 1.010101 (iv) 1.001001 (v) 0.666667 (vi) 0.909091 (vii) 0.990099 (viii) 0.999001 (b) 1 (c) y 苷 x ⫺ 3 5. (a) (i) ⫺32 ft兾s (ii) ⫺25.6 ft兾s (iii) ⫺24.8 ft兾s (iv) ⫺24.16 ft兾s (b) ⫺24 ft兾s 7. (a) (i) 4.65 m兾s (ii) 5.6 m兾s (iii) 7.55 m兾s (iv) 7 m兾s (b) 6.3 m兾s 9. (a) 0, 1.7321, ⫺1.0847, ⫺2.7433, 4.3301, ⫺2.8173, 0, ⫺2.1651, ⫺2.6061, ⫺5, 3.4202; no (c) ⫺31.4 EXERCISES 2.2 0 N N PAGE 96 1. Yes 3. (a) lim x l⫺3 f 共x兲 苷 ⬁ means that the values of f 共x兲 can be made arbitrarily large (as large as we please) by taking x sufficiently close to ⫺3 (but not equal to ⫺3). Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA065-075.qk_97909_Ans_Ans_pA065-A075 10/7/10 2:30 PM Page 71 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I (b) lim x l 4⫹ f 共x兲 苷 ⫺⬁ means that the values of f 共x兲 can be made arbitrarily large negative by taking x sufficiently close to 4 through values larger than 4. 5. (a) 2 (b) 1 (c) 4 (d) Does not exist (e) 3 7. (a) ⫺1 (b) ⫺2 (c) Does not exist (d) 2 (e) 0 (f) Does not exist (g) 1 (h) 3 9. (a) ⫺⬁ (b) ⬁ (c) ⬁ (d) ⫺⬁ (e) ⬁ (f) x 苷 ⫺7, x 苷 ⫺3, x 苷 0, x 苷 6 11. lim f 共x兲 exists for all a except a 苷 ⫺1. xla 13. (a) 1 15. (b) 0 (c) Does not exist 17. y y 2 (ii) ⫺5 49. (a) (i) 5 (c) 0 0 1 x x _1 1 2 9. 3 21. 5 23. 4 25. 29. ⫺⬁ 31. ⬁ 33. ⫺⬁ 39. ⫺⬁; ⬁ 41. (a) 2.71828 (b) 3 5 27. (a) ⫺1.5 35. ⫺⬁ 37. ⬁ 6 (2, 5) 0 _3 _3 4 _2 43. (a) 0.998000, 0.638259, 0.358484, 0.158680, 0.038851, 0.008928, 0.001465; 0 (b) 0.000572, ⫺0.000614, ⫺0.000907, ⫺0.000978, ⫺0.000993, ⫺0.001000; ⫺0.001 45. No matter how many times we zoom in toward the origin, the graph appears to consist of almost-vertical lines. This indicates more and more frequent oscillations as x l 0 . 47. x ⬇ ⫾0.90 , ⫾2.24 ; x 苷 ⫾sin⫺1共兾4兲 , ⫾共 ⫺ sin⫺1共兾4兲兲 EXERCISES 2.3 N x (2, _5) 51. (a) (i) ⫺2 (ii) Does not exist (iii) ⫺3 (b) (i) n ⫺ 1 (ii) n (c) a is not an integer. 57. 8 63. 15; ⫺1 N PAGE 116 1. 0.1 (or any smaller positive number) 3. 1.44 (or any smaller positive number) 5. 0.0906 (or any smaller positive number) 7. 0.011 (or any smaller positive number) 9. (a) 0.031 (b) 0.010 11. (a) s1000兾 cm (b) Within approximately 0.0445 cm (c) Radius; area; s1000兾 ; 1000; 5; ⬇0.0445 13. (a) 0.025 (b) 0.0025 35. (a) 0.093 (b) ␦ 苷 共B 2兾3 ⫺ 12兲兾共6B 1兾3 兲 ⫺ 1 , where B 苷 216 ⫹ 108 ⫹ 12 s336 ⫹ 324 ⫹ 81 2 41. Within 0.1 EXERCISES 2.5 _4 (b) Does not exist y EXERCISES 2.4 1 A71 N PAGE 127 1. lim x l 4 f 共x兲 苷 f 共4兲 3. (a) f 共⫺4兲 is not defined and lim f 共x兲 [for a 苷 ⫺2, 2, and 4] xla does not exist (b) ⫺4 , neither; ⫺2 , left; 2, right; 4, right 5. y 7. y 0 0 2 x 3 5 x PAGE 106 1. (a) ⫺6 (b) ⫺8 (c) 2 (d) ⫺6 (e) Does not exist (f) 0 7 3 3. 105 5. 8 7. 390 9. 2 11. 4 6 1 13. Does not exist 15. 5 17. ⫺10 19. 12 1 1 1 1 27. 128 29. ⫺2 21. 6 23. ⫺16 25. 1 2 31. 3x 2 33. (a), (b) 3 37. 7 41. 6 43. ⫺4 45. Does not exist y 47. (a) (b) (i) 1 (ii) ⫺1 1 (iii) Does not exist (iv) 1 0 x 9. (a) T 7 5 0 11. 4 7 10 16 19 24 t 17. f 共⫺2兲 is undefined. y y= 0 x=_2 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 1 x+2 x 97909_Ans_Ans_pA065-075.qk_97909_Ans_Ans_pA065-A075 10/7/10 2:30 PM Page 72 A72 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 19. lim f 共x兲 does not exist. 21. lim f 共x兲 苷 f 共0兲 39. (a), (b) ⫺2 43. y 苷 2; x 苷 ⫺2, x 苷 1 y y 2⫺x 49. f 共x兲 苷 2 x 共x ⫺ 3兲 53. ⫺⬁, ⫺⬁ y=≈ 1 y=´ 0 _π x 1 45. x 苷 5 51. (a) 5 4 23. Define f 共2兲 苷 3. 25. 共⫺⬁, ⬁兲 3 3 2 ) 傼 (s 2 , ⬁) 27. (⫺⬁, s 29. 关⫺1, 0兴 31. 共⫺⬁, ⫺1兴 傼 共0, ⬁兲 33. x 苷 0 47. y 苷 3 (b) 5 55. ⫺⬁, ⬁ y x 0 41. y 苷 2; x 苷 2 1 xl0 xl0 y 0 x 1 3 3 0 57. (a) 0 x 1 (b) An infinite number of times 1 4 _4 _1 7 35. 3 37. 1 41. 0, left -25 25 43. 0, right; 1, left y y _0.5 (1, e) (0, 2) (0, 2) 59. (a) 0 (1, 1) (0, 1) (0, 1) 0 x (2, 0) 63. (a) v * 0 (b) ⫾⬁ (b) 61. 5 ⬇ 0.47 s 1.2 x 45. 3 47. (a) t 共x兲 苷 x 3 ⫹ x 2 ⫹ x ⫹ 1 (b) t 共x兲 苷 x 2 ⫹ x 55. (b) 共0.86, 0.87兲 57. (b) 70.347 63. None 65. Yes 2 EXERCISES 2.6 N PAGE 140 65. N 艌 15 67. N 艋 ⫺6, N 艋 ⫺22 69. (a) x > 100 1. (a) As x becomes large, f 共x兲 approaches 5. (b) As x becomes large negative, f 共x兲 approaches 3. 3. (a) ⫺2 (b) 2 (c) ⬁ (d) ⫺⬁ (e) x 苷 1, x 苷 3, y 苷 ⫺2, y 苷 2 5. y=5 7. y 0 y x EXERCISES 2.7 N PAGE 150 f 共x兲 ⫺ f 共3兲 f 共x兲 ⫺ f 共3兲 1. (a) (b) lim x l 3 x⫺3 x⫺3 3. (a) 2 (b) y 苷 2x ⫹ 1 (c) 6 x=2 0 1 0 x y=_5 9. _1 y 5. y 苷 ⫺8x ⫹ 12 9. (a) 8a ⫺ 6a y=3 0 x (c) 2 7. y 苷 2 x ⫹ 1 0 5 1 2 (b) y 苷 2x ⫹ 3, y 苷 ⫺8x ⫹ 19 10 x=4 3 2 1 6 3 2 1 2 11. 0 13. 23. 3 31. ⫺⬁ 25. 27. 共a ⫺ b兲 1 33. 兾2 35. ⫺2 15. 17. 0 19. ⫺1 29. ⬁ 37. 0 21. 4 _2 4 _3 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA065-075.qk_97909_Ans_Ans_pA065-A075 10/7/10 2:30 PM Page 73 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 11. (a) Right: 0 ⬍ t ⬍ 1 and 4 ⬍ t ⬍ 6 ; left: 2 ⬍ t ⬍ 3 ; standing still: 1 ⬍ t ⬍ 2 and 3 ⬍ t ⬍ 4 (b) 49. The rate at which the temperature is changing at 8:00 AM; 3.75⬚F兾h 51. (a) The rate at which the oxygen solubility changes with respect to the water temperature; 共mg兾L兲兾⬚C (b) S⬘共16兲 ⬇ ⫺0.25; as the temperature increases past 16⬚C , the oxygen solubility is decreasing at a rate of 0.25 共mg兾L兲兾⬚C . 53. Does not exist v (m/s) 1 0 t (seconds) 1 EXERCISES 2.8 13. 15. 17. 19. 21. N PAGE 162 1. (a) ⫺0.2 (b) 0 (c) 1 (e) 1 (f) 0 (g) ⫺0.2 ⫺24 ft兾s ⫺2兾a 3 m兾s ; ⫺2 m兾s ; ⫺ 14 m兾s ; ⫺ 272 m兾s t⬘共0兲, 0, t⬘共4兲, t⬘共2兲, t⬘共⫺2兲 f 共2兲 苷 3; f ⬘共2兲 苷 4 (d) 2 y 2 fª 1 3 _3 y _2 1 0 5. 0 _1 3. (a) II x 1 1 (b) IV 2 x (c) I (d) III 7. y fª 23. y 苷 3x ⫺ 1 3 3 25. (a) ⫺ 5 ; y 苷 ⫺ 5 x ⫹ 16 5 y fª x 0 (b) A73 4 0 _1 x 6 _2 27. 33. 35. 37. 39. 41. 5 29. 共a ⫹ 3兲2 1 6a ⫺ 4 31. ⫺ s1 ⫺ 2a f 共x兲 苷 x 10, a 苷 1 or f 共x兲 苷 共1 ⫹ x兲10 , a 苷 0 f 共x兲 苷 2 x, a 苷 5 f 共x兲 苷 cos x, a 苷 or f 共x兲 苷 cos共 ⫹ x兲 , a 苷 0 1 m兾s ; 1 m兾s Temperature Greater (in magnitude) 72 (in °F) 38 9. 1 y fª fª x 0 0 y=C ª(t) Time 2 (in hours) 43. (a) (i) 23 million兾year 0 (ii) 20.5 million兾year (iii) 16 million兾year (b) 18.25 million兾year (c) 17 million兾year 45. (a) (i) $20.25兾unit (ii) $20.05兾unit (b) $20兾unit 47. (a) The rate at which the cost is changing per ounce of gold produced; dollars per ounce (b) When the 800th ounce of gold is produced, the cost of production is $17兾oz. (c) Decrease in the short term; increase in the long term x 13. (a) The instantaneous rate of change of percentage of full capacity with respect to elapsed time in hours (b) y The rate of change of percentage of full capacity is decreasing and 40 approaching 0. 20 0 11. y 15. 2 4 6 8 10 12 x 1963 to 1971 y 0.1 y=Mª(t) 0.05 _0.03 t 1950 1960 1970 1980 1990 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA065-075.qk_97909_Ans_Ans_pA065-A075 10/7/10 2:30 PM Page 74 A74 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 17. f ⬘共x兲 苷 e x y 53. f ⬘共x兲 苷 再 ⫺1 1 f, fª or f ⬘共x兲 苷 ⱍ 1 0 if x ⬍ 6 if x ⬎ 6 x⫺6 x⫺6 y fª 1 0 ⱍ x 6 _1 x 1 (b) ⫺1, ⫺2, ⫺4 19. (a) 0, 1, 2, 4 21. f ⬘共x兲 苷 2 , ⺢, ⺢ 1 (c) f ⬘共x兲 苷 2x 55. (a) (b) All x (c) f ⬘共x兲 苷 2 x y ⱍ ⱍ 23. f ⬘共t兲 苷 5 ⫺ 18t, ⺢, ⺢ 25. f ⬘共x兲 苷 2x ⫺ 6x 2 , ⺢, ⺢ 0 ⫺1 27. t⬘共x兲 苷 , 共⫺⬁, 9兴, 共⫺⬁, 9兲 2s9 ⫺ x ⫺7 , 共⫺⬁, ⫺3兲 傼 共⫺3, ⬁兲, 共⫺⬁, ⫺3兲 傼 共⫺3, ⬁兲 29. G⬘共t兲 苷 共3 ⫹ t兲2 31. f ⬘共x兲 苷 4x 3, ⺢, ⺢ 33. (a) f ⬘共x兲 苷 4x 3 ⫹ 2 35. (a) The rate at which the unemployment rate is changing, in percent unemployed per year (b) t U⬘共t兲 t U⬘共t兲 1999 2000 2001 2002 2003 ⫺0.2 0.25 0.9 0.65 ⫺0.15 2004 2005 2006 2007 2008 ⫺0.45 ⫺0.45 ⫺0.25 0.6 1.2 59. 63⬚ CHAPTER 2 REVIEW N PAGE 166 True-False Quiz 1. False 11. True 21. False 3. True 13. False 23. True 5. False 15. True 7. True 9. True 17. True 19. False Exercises 1. (a) (i) 3 (ii) 0 (iii) Does not exist (v) ⬁ (vi) ⫺⬁ (vii) 4 (viii) ⫺1 (b) y 苷 4 , y 苷 ⫺1 (c) x 苷 0 , x 苷 2 37. ⫺4 共corner兲; 0 共discontinuity兲 39. ⫺1 共vertical tangent兲; 4 共corner兲 41. 2 3. 1 5. 15. ⫺⬁ Differentiable at ⫺1; not differentiable at 0 _2 x 3 2 7. 3 17. 2 9. ⬁ 11. 19. 兾2 4 7 (iv) 2 (d) ⫺3, 0, 2, 4 13. 1 2 2 1. x 苷 0, y 苷 0 29. (a) (i) 3 (ii) 0 (iii) Does not exist (b) At 0 and 3 (c) y (iv) 0 (v) 0 23. 1 (vi) 0 3 1 _1 0 43. a 苷 f, b 苷 f ⬘, c 苷 f ⬙ 45. a 苷 acceleration, b 苷 velocity, c 苷 position 47. 6x ⫹ 2; 6 7 f· f x 31. ⺢ (b) y 苷 ⫺8x ⫹ 17 35. (a) ⫺8 37. (a) (i) 3 m兾s (ii) 2.75 m兾s (iii) 2.625 m兾s (iv) 2.525 m兾s (b) 2.5 m兾s 39. (a) 10 (b) y 苷 10 x ⫺ 16 (c) 12 fª _4 3 4 _1 –4 49. 3 f· f ⫺4 6 fª fªªª ⫺7 1 3 51. (a) a ⫺2兾3 f ⬘共x兲 苷 4x ⫺ 3x 2 , f ⬙共x兲 苷 4 ⫺ 6x , f 共x兲 苷 ⫺6 , f 共4兲共x兲 苷 0 4 –12 41. (a) The rate at which the cost changes with respect to the interest rate; dollars兾(percent per year) (b) As the interest rate increases past 10%, the cost is increasing at a rate of $1200兾(percent per year). (c) Always positive Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA065-075.qk_97909_Ans_Ans_pA065-A075 10/7/10 2:30 PM Page 75 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 43. 47. (a) v共t兲 苷 3t 2 ⫺ 3, a共t兲 苷 6t y x ] (b) (⫺⬁, 35 , (⫺⬁, 35 ) 45. (a) f ⬘共x兲 苷 ⫺ 2 共3 ⫺ 5x兲⫺1兾2 5 (c) (b) 12 m兾s2 (c) a共1兲 苷 6 m兾s2 49. (a) V 苷 5.3兾P (b) ⫺0.00212; instantaneous rate of change of the volume with respect to the pressure at 25⬚C; m3兾 kPa 51. 共⫺2, 21兲, 共1, ⫺6兲 1 1 55. y 苷 12x ⫺ 15, y 苷 12x ⫹ 17 57. y 苷 3 x ⫺ 3 3 3 9 2 59. 共⫾2, 4兲 63. P共x兲 苷 x ⫺ x ⫹ 3 65. y 苷 16 x ⫺ 4 x ⫹ 3 67. No y y fª 0 6 2 f (1, 2) fª 0 _6 5 (vertical tangent) 49. The rate at which the total value of US currency in circulation is changing in billions of dollars per year; $22.2 billion兾year 51. 0 f ⬘共x兲 苷 再 (b) y y ƒ (b) 1 (c) Yes; no ⫺3 0 PAGE 181 50 1 N 11. F⬘共 y兲 苷 5 ⫹ 25. 27. 33. 7. t⬘共x兲 苷 14 9 ⫹ 4 y2 y x 2共3 ⫺ x 2兲 共1 ⫺ x 2兲 2 35. (a) y 苷 2 x ⫹ 1 1 ⫺3 ⫺10 3. f ⬘共x兲 苷 e x共x 3 ⫹ 3x 2 ⫹ 2x ⫹ 2兲 10 共3 ⫺ 4x兲2 15. y⬘ 苷 (b) 1.5 5 (_1, 0.5) ⫺40 43. f ⬘共x兲 苷 100x 9 ⫹ 25x 4 ⫺ 1; f ⬙共x兲 苷 900x 8 ⫹ 100x 3 15 4 x⫺1兾4, f ⬙共x兲 苷 15 16 x⫺5兾4 9. H⬘共u兲 苷 2u ⫺ 1 2t共⫺t 4 ⫺ 4t 2 ⫹ 7兲 共t 4 ⫺ 3t 2 ⫹ 1兲 2 3 p y⬘ 苷 e (1 ⫹ 2 sp ⫹ p ⫹ psp ) 19. y⬘ 苷 2v ⫺ 1兾sv 1兾2 4⫹t ⫺ACe x f ⬘共t兲 苷 23. f ⬘共x兲 苷 2 (2 ⫹ st ) 共B ⫹ Ce x 兲 2 2cx f ⬘共x兲 苷 2 共x ⫹ c兲2 4 共x ⫹ 4x 3兲e x; 共x 4 ⫹ 8x 3 ⫹ 12x 2 兲e x 2 2x 2 ⫹ 2x 2 2 ; 31. y 苷 3 x ⫺ 3 2 共1 ⫹ 2x兲 共1 ⫹ 2x兲3 y 苷 2x ; y 苷 ⫺ 12 x 13. y⬘ 苷 21. 75. m 苷 4, b 苷 ⫺4 PAGE 189 1⫺x 5. y⬘ 苷 ex 29. 100 73. a 苷 ⫺ 2 , b 苷 2 1. 1 ⫺ 2x ⫹ 6x 2 ⫺ 8x 3 17. x 79. 3; 1 EXERCISES 3.2 (b) 0.99, 1.03; 2.7 ⬍ e ⬍ 2.8 2 3. f ⬘共x兲 苷 0 5. f ⬘共t兲 苷 ⫺3 7. f ⬘共x兲 苷 3x 2 ⫺ 4 2 9. t⬘共x兲 苷 2x ⫺ 6x 11. t⬘共t兲 苷 ⫺ 32 t ⫺7兾4 13. A⬘共s兲 苷 60兾s 6 1 15. R⬘共a兲 苷 18a ⫹ 6 17. S⬘共 p兲 苷 2 p⫺1兾2 ⫺ 1 19. y⬘ 苷 3e x ⫺ 43 x ⫺4兾3 21. h⬘共u兲 苷 3Au 2 ⫹ 2Bu ⫹ C 2 3 3 23. y⬘ 苷 2 sx ⫹ 25. j⬘共x兲 苷 2.4 x 1.4 ⫺ 2xsx sx 27. H⬘共x兲 苷 3x 2 ⫹ 3 ⫺ 3x ⫺2 ⫺ 3x ⫺4 1 29. u⬘ 苷 5 t ⫺4兾5 ⫹ 10t 3兾2 1 3 31. z⬘ 苷 ⫺10A兾y 11 ⫹ Be y 33. y 苷 4 x ⫹ 4 1 35. Tangent: y 苷 2x ⫹ 2; normal: y 苷 ⫺2 x ⫹ 2 37. y 苷 3x ⫺ 1 39. f ⬘共x兲 苷 4 x 3 ⫺ 6x 2 ⫹ 2x 41. (a) (c) 4x 3 ⫺ 9x 2 ⫺ 12x ⫹ 7 3 x 3 71. y 苷 2x 2 ⫺ x 1. (a) See Definition of the Number e (page 180). 45. f ⬘共x兲 苷 2 ⫺ ƒ⬘ ⫺3 CHAPTER 3 5 x ⱍ ⱍ ⱍ ⱍ 9 77. 1000 ⫺3 1 0 2 N 0 if x ⬎ 3 if x ⬍ 3 2x ⫺2x PAGE 170 1. 3 3. ⫺4 5. (a) Does not exist 1 1 3 7. a 苷 2 ⫾ 2 s5 9. 4 11. (b) Yes 13. (a) 0 (b) 1 (c) f ⬘共x兲 苷 x 2 ⫹ 1 EXERCISES 3.1 y=fª(x) x 69. (a) Not differentiable at 3 or ⫺3 47. ⫺4 (discontinuity), ⫺1 (corner), 2 (discontinuity), N 1 y=ƒ 1 _3 PROBLEMS PLUS A75 ⫺4 4 ⫺0.5 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA076-085.qk_97909_Ans_Ans_pA076-085 10/7/10 2:32 PM Page 76 A76 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 37. (a) e x 共x 3 3x 2 x 1兲 (b) 37. 5 ft兾rad 2 45. fª 10 2 f _2 (a) f 共x兲 苷 39. 4共1 3x 2 兲 4x ; f 共x兲 苷 2 共x 1兲 共x 2 1兲3 f· fª _6 41. 47. s2 (b) (c) 20 45. 7 2 xt共x兲 t共x兲 t共x兲 xt共x兲 (b) y 苷 (c) y 苷 2 关t共x兲兴 x2 1 53. Two, (2 s3, 2 (1 s3 )) 55. 1 57. $1.627 billion兾year 59. (c) 3e 3x 61. f 共x兲 苷 共x 2 2x兲e x, f 共x兲 苷 共x 2 4x 2兲e x, f 共x兲 苷 共x 2 6x 6兲e x, f 共4兲共x兲 苷 共x 2 8x 12兲e x, f 共5兲共x兲 苷 共x 2 10x 20兲e x; f (n)共x兲 苷 关x 2 2nx n共n 1兲兴e x N PAGE 205 1 s1 2x 11. f 共z兲 苷 PAGE 197 1 2 tan x x sec 2 x sec tan 11. f 共 兲 苷 共2 tan x兲 2 共1 sec 兲2 共t 2 t兲 cos t sin t y 苷 共1 t兲2 f 共x兲 苷 e x csc x 共x cot x x 1兲 y 苷 2s3x 23 s3 2 23. y 苷 x 1 (a) y 苷 2 x (b) 3π 9. y 苷 25. 15. y 苷 ekx 共k x 1兲 2 12 x 共x 2 1兲 2 共x 2 1兲 4 25. y 苷 51兾x共ln 5兲兾x 2 23. y 苷 3e 3x s1 2e 3x 27. y 苷 共r 2 1兲3兾2 29. F共t兲 苷 e t sin 2t 共2t cos 2t sin 2t兲 33. y 苷 2sin x共 31. y 苷 2 cos共tan 2x兲 sec 2 共2x兲 35. y 苷 ln 2兲 cos x 4e 1e sin 共1 e 2x 兲 2 1 e 2x 2x 2x 37. y 苷 2 cos cot共sin 兲 csc 2 共sin 兲 39. f 共t兲 苷 sec 共e 兲e t e tan t sec 2t 2 t 41. f 共t兲 苷 4 sin 共e sin t 兲 cos 共e sin t 兲 e sin t sin t cos t 1. f 共x兲 苷 6x 2 sin x 3. f 共x兲 苷 cos x 2 csc2x 2 2 5. y 苷 sec 共sec tan 兲 7. y 苷 c sin t t共t cos t 2 sin t兲 21. 2z 共z 2 1兲2 19. h共t兲 苷 3 共t 1兲1兾3共2t 2 1兲 2 共20t 2 18t 1兲 2 15. 1 1 sin x (b) sec x tan x 苷 2 cos x cos 2x cot x 1 (c) cos x sin x 苷 csc x 55. 1 21. y 苷 49. (a) 0 (b) 3 51. (a) y 苷 xt共x兲 t共x兲 13. 3 17. f 共x兲 苷 共2x 3兲 3 共x 2 x 1兲 4 共28x 2 12x 7兲 20 9 47. y 苷 2x 18 EXERCISES 3.3 51. A 苷 10, B 苷 10 49. cos x 13. y 苷 3x 2 sin共a 3 x 3 兲 43. (a) 16 N 3 53. (a) sec 2x 苷 9. F共x兲 苷 6 _2 1 4 43. 4 41. 3 4 e sx 2 1. 3 3. sec x 5. 3s共1 4x兲2 2sx 7. F共x兲 苷 10 x共x 4 3x 2 2兲 4 共2x 2 3兲 4 f 39. 3 EXERCISES 3.4 2 (b) 1 2 2 2 43. t共x兲 苷 2r 2 p共ln a兲 共2ra rx n兲 p1 a rx x兲 sec 2 共 x兲 sinssin 共tan x兲 2ssin 共tan x兲 47. y 苷 2x sin共x 2 兲; y 苷 4x 2 cos共x 2 兲 2 sin共x 2 兲 45. y 苷 cos共tan 49. e x共 cos x e x 关共 2 2兲 sin x 51. y 苷 20x 1 1 55. (a) y 苷 2 x 1 sin x兲; 2 cos x兴 53. y 苷 x (b) 3 (0, 1) 2 _3 π 3 ” 2 , π’ _1.5 0 π 27. (a) sec x tan x 1 29. 31. 33. 35. (b) cos sin ; 2 cos sin (a) f 共x兲 苷 共1 tan x兲兾sec x (b) f 共x兲 苷 cos x sin x 共2n 1兲 13 , n an integer (a) v共t兲 苷 8 cos t, a共t兲 苷 8 sin t 4 s3, 4, 4s3; to the left 59. 61. 65. 2 2x 2 (a) f 共x兲 苷 s2 x 2 共共 兾2兲 2n , 3兲, 共共3 兾2兲 2n , 1兲, n an integer 24 63. (a) 30 (b) 36 (a) 34 (b) Does not exist (c) 2 67. 69. 71. 77. 16 s2 (a) F共x兲 苷 e x f 共e x 兲 (b) G共x兲 苷 e f 共x兲 f 共x兲 120 73. 96 5 250 cos 2x 79. v共t兲 苷 2 cos共10 t兲 cm兾s 57. Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA076-085.qk_97909_Ans_Ans_pA076-085 10/7/10 2:32 PM Page 77 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I dB 7 2 t (b) 0.16 苷 cos dt 54 5.4 83. v 共t兲 苷 2e1.5t共2 cos 2 t 1.5 sin 2 t兲 81. (a) 2 53. G共x兲 苷 1 x arccos x s1 x 2 57. y 苷 sin1 x 59. y 苷 15 61. 1 √ s 0 2 1 55. h共t兲 苷 0 sa 2 b 2 a b cos x x arcsin x s1 x 2 65. 0 67. y y 2 7 x 85. dv兾dt is the rate of change of velocity with respect to time; dv兾ds is the rate of change of velocity with respect to displacement 87. (a) y 苷 ab t where a ⬇ 100.01244 and b ⬇ 0.000045146 (b) 670.63 A 89. (b) The factored form 93. (b) n cos n1x sin关共n 1兲x兴 EXERCISES 3.5 PAGE 215 N 1. (a) y 苷 9x兾y (b) y 苷 s9x 2 1, y 苷 9x兾s9x 2 1 3. (a) y 苷 y 2兾x 2 (b) y 苷 x兾共x 1兲, y 苷 1兾共x 1兲2 x2 2x y 5. y 苷 2 7. y 苷 y 2y x 3y 2 5x 4 4x 3 y 2x y sin x 9. y 苷 4 11. y 苷 2 x 3y 6xy cos x 2y y共 y e x兾y 兲 13. y 苷 tan x tan y 15. y 苷 2 y xe x兾y 4 2 2 4 4 1 x y y x y 2xy 17. y 苷 x 2 2xy 2x 5y 3 y e sin x y cos共x y兲 16 19. y 苷 y 21. 13 e cos x x cos共x y兲 2x 4y x 3 6xy 2 23. x 苷 25. y 苷 12 x 4x 3y 2 3x 2 y 2y 3 1 9 40 27. y 苷 x 2 29. y 苷 x 2 31. y 苷 13 x 13 9 5 (b) 33. (a) y 苷 2 x 2 5 x V 3共nb V 兲 (b) 4.04 L兾atm PV n2aV 2n3ab 73. (s3, 0) 75. 共1, 1兲, 共1, 1兲 77. (b) 79. (a) 0 (b) 12 71. (a) 3 EXERCISES 3.6 N 3 2 PAGE 223 1. The differentiation formula is simplest. cos共ln x兲 1 5. f 共x兲 苷 x x 3x 2 sin x 7. f 共x兲 苷 3 9. f 共x兲 苷 cos x ln共5x兲 共x 1兲 ln 10 x 2x 2 1 y 10 11. t共x兲 苷 13. G共 y兲 苷 2 x 共x 2 1兲 2y 1 y 1 1 a 15. F共s兲 苷 17. y 苷 sec 2共ln共ax b兲兲 s ln s ax b x 1 19. y 苷 21. y 苷 log10 x ln 10 1x 3. f 共x兲 苷 23. y 苷 x 2x ln共2x兲; y 苷 3 2 ln共2x兲 1 x 25. y 苷 ; y 苷 共1 x 2 兲 3兾2 s1 x 2 2x 1 共x 1兲 ln共x 1兲 ; 共x 1兲关1 ln共x 1兲兴 2 共1, 1 e兲 傼 共1 e, 兲 2共x 1兲 ; 共, 0兲 傼 共2, 兲 29. f 共x兲 苷 x 共 x 2兲 27. f 共x兲 苷 (1, 2) _2 2 _2 35. 81兾y 41. (a) 3 37. 2x兾y 5 39. 1兾e 2 Eight; x ⬇ 0.42, 1.58 4 33. y 苷 3x 9 5 冑 x1 x4 1 1 1 (b) y 苷 x 1, y 苷 3 x 2 (c) 1 3 s3 5 5 43. ( 4 s3, 4 ) 45. 共x0 x兾a 2 兲 共 y0y兾b 2 兲 苷 1 1 2 tan x 1 49. y 苷 51. y 苷 1 x2 sx 2 x 冉 冉 冉 16x 3 4x 4 x 2 x 4 2 51. y 苷 冉 ln tan x sec2 x x tan x x2 2x x y 2 2y 2 冊 冊 冊 sin x cos x ln x x 47. y 苷 共cos x兲 x共x tan x ln cos x兲 49. y 苷 共tan x兲1兾x 31. 1 37. 7 1 2x 3 4 2x 2 x 1 43. y 苷 x x共1 ln x兲 45. y 苷 x sin x _3 35. cos x 1兾x 39. y 苷 共x 2 2兲 2 共x 4 4兲 4 41. y 苷 _2 A77 冊 53. f 共n兲共x兲 苷 共1兲n1共n 1兲! 共x 1兲n Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA076-085.qk_97909_Ans_Ans_pA076-085 10/7/10 2:32 PM Page 78 A78 APPENDIX I EXERCISES 3.7 ANSWERS TO ODD-NUMBERED EXERCISES PAGE 233 N 1. (a) 3t 24t 36 (b) 9 ft兾s (c) t 苷 2, 6 (d) 0 t 2, t 6 (e) 96 ft (g) 6t 24; 6 ft兾s2 (f) t 8, 2 s 32 t 6, s0 t 2, s 32 t 0, s0 0 (h) s 20 (i) Speeding up when 2 t 4 or t 6; slowing down when 0 t 2 or 4 t 6 40 s √ 0 8 a 25 冉 冊 t 1 sin (b) 8 s2 ft兾s 4 4 (d) 4 t 8 (e) 4 ft (f) t =10, 3. (a) s=0 t 8, s 1 t 4, s _1 t 0, s 1 s 0 (g) 161 (h) 1 (c) t 苷 0, 4, 8 2 cos共 t兾4兲; 321 s 2 s2 ft兾s 2 a 8 0 √ _1 (i) Speeding up when 0 t 2, 4 t 6, 8 t 10; slowing down when 2 t 4, 6 t 8 5. (a) Speeding up when 0 t 1 or 2 t 3; slowing down when 1 t 2 (b) Speeding up when 1 t 2 or 3 t 4; slowing down when 0 t 1 or 2 t 3 5 7. (a) 4.9 m兾s; 14.7 m兾s (b) After 2.5 s (c) 32 16 m (d) ⬇5.08 s (e) ⬇25.3 m兾s 9. (a) 7.56 m兾s (b) 6.24 m兾s; 6.24 m兾s 11. (a) 30 mm2兾mm; the rate at which the area is increasing with respect to side length as x reaches 15 mm (b) A ⬇ 2x x 13. (a) (i) 5 (ii) 4.5 (iii) 4.1 (b) 4 (c) A ⬇ 2 r r 15. (a) 8 ft 2兾ft (b) 16 ft 2兾ft (c) 24 ft 2兾ft The rate increases as the radius increases. 17. (a) 6 kg兾m (b) 12 kg兾m (c) 18 kg兾m At the right end; at the left end 2 19. (a) 4.75 A (b) 5 A; t 苷 3 s 23. (a) dV兾dP 苷 C兾P 2 (b) At the beginning 25. 400共3t 兲 ln 3; ⬇ 6850 bacteria兾h 27. (a) 16 million兾year; 78.5 million兾year (b) P共t兲 苷 at 3 bt 2 ct d, where a ⬇ 0.00129371, b ⬇ 7.061422, c ⬇ 12,822.979, d ⬇ 7,743,770 (c) P共t兲 苷 3at 2 2bt c (d) 14.48 million兾year; 75.29 million兾year (smaller) (e) 81.62 million兾year 29. (a) 0.926 cm兾s; 0.694 cm兾s; 0 (b) 0; 92.6 共cm兾s兲兾cm; 185.2 共cm兾s兲兾cm (c) At the center; at the edge 31. (a) C共 x 兲 苷 12 0.2 x 0.0015x 2 (b) $32兾yard ; the cost of producing the 201st yard (c) $32.20 33. (a) 关xp共x兲 p共x兲兴兾x 2; the average productivity increases as new workers are added. 35. 0.2436 K兾min 37. (a) 0 and 0 (b) C 苷 0 (c) 共0, 0兲, 共500, 50兲; it is possible for the species to coexist. EXERCISES 3.8 N PAGE 242 1. About 235 3. (a) 100共4.2兲 t (b) ⬇7409 (c) ⬇10,632 bacteria兾h (d) 共ln 100兲兾共ln 4.2兲 ⬇ 3.2 h 5. (a) 1508 million, 1871 million (b) 2161 million (c) 3972 million; wars in the first half of century, increased life expectancy in second half 7. (a) Ce0.0005t (b) 2000 ln 0.9 ⬇ 211 s 9. (a) 100 2t兾30 mg (b) ⬇ 9.92 mg (c) ⬇199.3 years 11. ⬇2500 years 13. (a) ⬇137F (b) ⬇116 min 15. (a) 13.3C (b) ⬇67.74 min 17. (a) ⬇64.5 kPa (b) ⬇39.9 kPa 19. (a) (i) $3828.84 (ii) $3840.25 (iii) $3850.08 (iv) $3851.61 (v) $3852.01 (vi) $3852.08 (b) dA兾dt 苷 0.05A, A共0兲 苷 3000 EXERCISES 3.9 N PAGE 248 1. dV兾dt 苷 3x 2 dx兾dt 3. 48 cm 2兾s 5. 3兾共25 兲 m兾min 7. (a) 1 (b) 25 9. 18 11. (a) The plane’s altitude is 1 mi and its speed is 500 mi兾h. (b) The rate at which the distance from the plane to the station is increasing when the plane is 2 mi from the station (c) (d) y 2 苷 x 2 1 x (e) 250 s3 mi兾h 1 y 13. (a) The height of the pole (15 ft), the height of the man (6 ft), and the speed of the man (5 ft兾s) (b) The rate at which the tip of the man’s shadow is moving when he is 40 ft from the pole 15 xy (c) (d) (e) 253 ft兾s 苷 6 y 15 6 x y 15. 65 mi兾h 17. 837兾s8674 ⬇ 8.99 ft兾s 720 19. 1.6 cm兾min 21. 13 ⬇ 55.4 km兾h Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA076-085.qk_97909_Ans_Ans_pA076-085 10/7/10 2:32 PM Page 79 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 23. 共10,000 800,000 兾9兲 ⬇ 2.89 10 5 cm3兾min 10 25. 3 cm兾min 27. 6兾共5 兲 ⬇ 0.38 ft兾min 29. 0.3 m 2兾s 107 33. 80 cm 3兾min 35. 810 ⬇ 0.132 兾s 31. 5 m (b) 0.096 rad兾s 37. 0.396 m兾min 39. (a) 360 ft兾s 10 41. 9 km兾min 43. 1650兾s31 ⬇ 296 km兾h 45. 4 s15 ⬇ 6.78 m兾s 7 EXERCISES 3.10 N PAGE 255 1. L共x兲 苷 10x 6 3. L共x兲 苷 4 x 1 1 5. s1 x ⬇ 1 x ; 1 2 3 y=1- 21 x s0.9 ⬇ 0.95, s0.99 ⬇ 0.995 y=œ„„„„ 1-x 3 (1, 0) _1 11. (a) 13. (a) 15. (a) 17. (a) 19. y 9. 0.368 x 0.677 t dy 苷 2x共x cos 2x sin 2x兲 dx (b) dy 苷 dt 1 t2 2 4 v sec st dy 苷 dt (b) dy 苷 dv 共1 v 2兲2 2st dy 苷 101 e x兾10 dx (b) 0.01 x dx (b) 0.05 dy 苷 s3 x 2 苷 0.64, dy 苷 0.8 y dy Îy 0 1 dx=Îx 21. y 苷 0.1, dy 苷 0.125 y dx=Îx Îy 2 y= x 2 1. True 11. True dy 27. 1 25. 10.003 7. 8t 3 共t 1兲2 4 13. 3 9. 1 ln x x ln x e1兾x共1 2x兲 x4 (b) 36 cm , 0.006, 0.6% ⬇ 27 cm 2; 841 ⬇ 0.012 苷 1.2% 1 (b) 1764兾 2 ⬇ 179 cm 3; 56 ⬇ 0.018 苷 1.8% 37. (a) 2 rh r (b) 共r兲2h 43. (a) 4.8, 5.2 (b) Too large 9. True 1 1 2sx sx 3 cos sx sx sin sx 2sx 2xy cos y 15. 1 x sin y x 2 11. 冉 冊 1 1 t2 t 19. sec2 2 共1 t 2兲2 1 t2 2sarctan x 共1 x 兲 21. 3 x ln x共ln 3兲共1 ln x兲 23. 共x 1兲2 2 2x y cos共xy兲 25. 27. x cos共xy兲 1 共1 2x兲 ln 5 4x 29. cot x sin x cos x 31. tan1共4x兲 1 16x 2 33. 5 sec 5x 35. 6x csc 2 共3x 2 5兲 3x 2 37. cos(tan s1 x 3 )(sec 2s1 x 3 ) 2 s1 x 3 2 39. 2 cos tan共sin 兲 sec 共sin 兲 49. 2 33. (a) 270 cm , 0.01, 1% 35. (a) 84兾 兾90 ⬇ 0.965 7. False 3. 2 sx 5. x共 x cos x 2 sin x兲 45. x 3 5. False 15. True 1. 4x 7共x 1兲 3共3x 2兲 1 23. 15.968 3. True 13. True Exercises 41. 0 1 PAGE 264 17. y=2x-≈ 1 N True-False Quiz _3 7. 0.383 x 0.516 23. (a) 1 (b) 1 (c) (d) (e) 0 (f) 1 (g) (h) (i) 0 31. f 共x兲 苷 x cosh x 33. h共x兲 苷 tanh x 35. y 苷 3e cosh 3x sinh 3x 37. f 共 t 兲 苷 2e t sech 2 共e t 兲 tanh共e t 兲 1 2 sinh x 39. G共x兲 苷 41. y 苷 共1 cosh x兲2 2sx共x 1兲 43. y 苷 sinh1共x兾3兲 45. y 苷 csc x 51. (a) 0.3572 (b) 70.34° 53. (a) 164.50 m (b) 120 m; 164.13 m 55. (b) y 苷 2 sinh 3x 4 cosh 3x 57. ( ln 共1 s2 ), s2 ) CHAPTER 3 REVIEW (0, 1) 53. 59. 63. 共x 2兲4共3x 2 55x 52兲 43. 2x 2 cosh共x 2 兲 sinh共x 2 兲 2 sx 1 共x 3兲8 cosh x 47. 3 tanh 3x ssinh 2x 1 3 sin (e stan 3x ) e stan 3x sec 2共3x兲 4 51. 27 2stan 3x 57. y 苷 2s3x 1 s3兾3 5x 4兾y 11 61. y 苷 x 2; y 苷 x 2 y 苷 2x 1 10 3x 7 1 (b) y 苷 4 x 4 , y 苷 x 8 (a) 2 s5 x 10 (c) (4, 4) EXERCISES 3.11 N PAGE 262 _10 1. (a) 0 (b) 1 3. (a) 4 (b) 2 共e 2 e2 兲 ⬇ 3.62686 5. (a) 1 (b) 0 3 4 3 4 5 21. sech x 苷 5 , sinh x 苷 3 , csch x 苷 4 , tanh x 苷 5 , coth x 苷 4 3 A79 (1, 2) 10 1 ƒ _10 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA076-085.qk_97909_Ans_Ans_pA076-085 10/7/10 2:32 PM Page 80 A80 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 65. ( 兾4, s2 ), (5 兾4, s2 ) 69. (a) 2 71. 2xt共x兲 x 2t共x兲 73. 2t共x兲t共x兲 11. (a) (b) 44 0 1 0 x 3 1 2 3 x _1 y 2 1 a v 0 0 2 _1 (c) y 1 1 f 共x兲关t共 x兲兴 2 t共x兲 关 f 共x兲兴 2 75. t共e x 兲e x 77. t共x兲兾t共x兲 79. 关 f 共x兲 t共x兲兴 2 81. f 共t共sin 4x兲兲t共sin 4x兲共cos 4x兲共4兲 2 14 83. 共3, 0兲 85. y 苷 3 x 2 3 x ct 87. v共t兲 苷 Ae 关c cos共t 兲 sin共t 兲兴, a共t兲 苷 Aect 关共c 2 2 兲 cos共t 兲 2c sin共t 兲兴 89. (a) v 共t兲 苷 3t 2 12; a共t兲 苷 6t (b) t 2; 0 t 2 (c) 23 (d) 20 (e) t 2; 0 t 2 y (b) y 1 2 x 3 _1 t 3 position 15 13. (a) 91. 4 kg兾m 93. (a) 200共3.24兲 t PROBLEMS PLUS 1. (s3兾2, 1 4 ) PAGE 269 N 5. 3s2 11. (0, 5 4 ) (b) 40 (cos s8 cos 2 480 sin (1 cos 兾s8 cos 2 ) cm兾s xT 僆 共3, 兲, y T 僆 共2, 兲, xN 僆 (0, 53 ), yN 僆 (52 , 0) (b) (i) 53 (or 127 ) (ii) 63 (or 117 ) R approaches the midpoint of the radius AO. 25. 2se 29. 共1, 2兲, 共1, 0兲 sin a 375 33. 2 128 ⬇ 11.204 cm3兾min s29兾58 13. (a) 4 s3兾s11 rad兾s (c) 17. 19. 21. 23. 31. ) cm (b) y (b) ⬇22,040 (c) ⬇25,910 bacteria兾h (d) 共ln 50兲兾共ln 3.24兲 ⬇ 3.33 h 4 95. (a) C 0 ekt (b) ⬇100 h 97. 3 cm2兾min 99. 13 ft兾s 101. 400 ft兾h 3 3 1 3x ⬇ 1 x; s 1.03 ⬇ 1.01 103. (a) L共x兲 苷 1 x; s (b) 0.235 x 0.401 1 1 3 1 105. 12 2 ⬇ 16.7 cm 2 107. 32 109. 4 111. 8 x 2 y _1 0 15. 19. 21. 23. 27. 35. 43. 49. 53. x 2 0 x Abs max f 共3兲 苷 4 17. Abs max f 共1兲 苷 1 Abs min f 共0兲 苷 0 Abs max f 共 兾2兲 苷 1; abs min f 共 兾2兲 苷 1 Abs max f 共2兲 苷 ln 2 25. Abs max f 共0兲 苷 1 1 Abs max f 共3兲 苷 2 29. 3 31. 2, 3 33. 0 4 8 0, 2 37. 0, 9 39. 0, 7, 4 41. n 共n an integer兲 0, 23 45. 10 47. f 共2兲 苷 16, f 共5兲 苷 7 f 共1兲 苷 8 , f 共2兲 苷 19 51. f 共2兲 苷 33, f 共2兲 苷 31 55. f (s2 ) 苷 2 , f 共1兲 苷 s3 f 共0.2兲 苷 5.2, f 共1兲 苷 2 57. f 共 兾6兲 苷 2s3, f 共 兾2兲 苷 0 3 8 59. f 共2兲 苷 2兾se , f 共1兲 苷 1兾s e 61. f 共1兲 苷 ln 3, f ( 2 ) 苷 ln 4 1 CHAPTER 4 EXERCISES 4.1 N PAGE 280 63. f Abbreviations: abs, absolute; loc, local; max, maximum; min, minimum 9. y y 3 3 2 2 1 1 0 1 2 3 4 5 x 0 1 2 3 4 5 a ab 苷 a abb 共a b兲ab 6 6 (b) 25 s35 2, 25 s35 2 3 67. (a) 0.32, 0.00 (b) 16 s3, 0 69. ⬇3.9665C 71. Cheapest, t ⬇ 0.855 (June 1994); most expensive, t ⬇ 4.618 (March 1998) 65. (a) 2.19, 1.81 1. Abs min: smallest function value on the entire domain of the function; loc min at c: smallest function value when x is near c 3. Abs max at s, abs min at r, loc max at c, loc min at b and r, neither a max nor a min at a and d 5. Abs max f 共4兲 苷 5 , loc max f 共4兲 苷 5 and f 共6兲 苷 4 , loc min f 共2兲 苷 2 and f 共1兲 苷 f 共5兲 苷 3 7. 冉 冊 3 x 73. (a) r 苷 3 r0 2 (c) 4 (b) v 苷 27 kr 30 √ 4 27 kr#̧ 0 2 3 r¸ r¸ r Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA076-085.qk_97909_Ans_Ans_pA076-085 10/7/10 2:32 PM Page 81 APPENDIX I EXERCISES 4.2 N PAGE 288 29. ANSWERS TO ODD-NUMBERED EXERCISES A81 y 9 4 1. 2 3. 5. f is not differentiable on (1, 1) 7. 0.3, 3, 6.3 9. 1 11. 3兾 ln 4 13. 1 15. f is not continous at 3 23. 16 25. No 31. No EXERCISES 4.3 N PAGE 297 Abbreviations: inc, increasing; dec, decreasing; CD, concave downward; CU, concave upward; HA, horizontal asymptote; VA, vertical asymptote; IP, inflection point(s) 1. (a) 共1, 3兲, 共4, 6兲 (b) 共0, 1兲, 共3, 4兲 (d) 共2, 4兲, 共4, 6兲 (e) 共2, 3兲 (c) 共0, 2兲 3. (a) I / D Test (b) Concavity Test (c) Find points at which the concavity changes. 5. (a) Inc on 共1, 5兲; dec on 共0, 1兲 and 共5, 6兲 (b) Loc max at x 苷 5, loc min at x 苷 1 7. (a) 3, 5 (b) 2, 4, 6 (c) 1, 7 11. (a) Inc on 共1, 0兲, 共1, 兲; dec on 共, 1兲, 共0, 1兲 (b) Loc max f 共0兲 苷 3; loc min f 共1兲 苷 2 (c) CU on (, s3兾3), (s3兾3, ); CD on (s3兾3, s3兾3); IP (s3兾3, 229) 兾4兲, 共5 兾4, 2 兲; dec on 共 兾4, 5 兾4兲 (b) Loc max f 共 兾4兲 苷 s2 ; loc min f 共5 兾4兲 苷 s2 (c) CU on 共3 兾4, 7 兾4兲; CD on 共0, 3 兾4兲, 共7 兾4, 2 兲; IP 共3 兾4, 0兲, 共7 兾4, 0兲 13. (a) Inc on 共0, 15. (a) Inc on ( ln 2, ); dec on (, ln 2) (b) Loc min f ( ln 2) 苷 22兾3 21兾3 (c) CU on 共, 兲 1 3 17. (a) Inc on 共1, 兲; dec on 共0, 1兲 (b) Loc min f 共1兲 苷 0 (c) CU on 共0, 兲; No IP 19. Loc max f 共1兲 苷 2; loc min f 共0兲 苷 1 21. Loc min f (16 ) 苷 4 1 1 23. (a) f has a local maximum at 2. (b) f has a horizontal tangent at 6. 27. 1 2 3 4 0 2 0 2 2 4 x _2 0 2 8 x 1 23 ’ 9 6 x (2, _14) 35. (a) Inc on 共, 1兲, 共0, 1兲; dec on 共1, 0兲, 共1, 兲 (b) Loc max f 共1兲 苷 3, f 共1兲 苷 3; loc min f 共0兲 苷 2 (c) CU on (1兾s3, 1兾s3 ); CD on (, 1兾s3 ), 共1兾s3, ); IP (1兾s3, 239) (d) See graph at right. 39. (a) Inc on 共, 4兲; dec on 共4, 6兲 (b) Loc max f 共4兲 苷 4s2 (c) CD on 共, 6兲; No IP (d) See graph at right. y x=2 0 1 ”_ œ„3 , y 23 ’ 9 (_1, 3) x ” œ„3 , (1, 3) 1 0 1 x y 7 (_2, 7) (_1, 3) _1 x y _2 _2 37. (a) Inc on 共, 2兲, 共0, 兲; dec on 共2, 0兲 (b) Loc max h 共2兲 苷 7; loc min h 共0兲 苷 1 (c) CU on 共1, 兲; CD on 共, 1兲; IP 共1, 3兲 (d) See graph at right. y 0 y (_2, 18) (b) Loc max f 共3兲 苷 81; loc min f 共2兲 苷 44 (c) CU on 共12, 兲; CD on (, 12); IP ( 12, 372 ) 1 3 1 3 31. (a) Inc on (0, 2), (4, 6), 共8, 兲; dec on (2, 4), (6, 8) (b) Loc max at x 苷 2, 6; loc min at x 苷 4, 8 (c) CU on (3, 6), 共6, 兲; CD on (0, 3) (d) 3 (e) See graph at right. 33. (a) Inc on 共, 2兲, 共2, 兲; dec on 共2, 2兲 (b) Loc max f 共2兲 苷 18; loc min f 共2兲 苷 14 (c) CU on 共0, 兲, CD on 共, 0兲; IP 共0, 2兲 (d) y 9. (a) Inc on 共, 3兲, 共2, 兲; dec on 共3, 2兲 25. x 0 y x (0, _1) { 4, 4œ„2 } 0 4 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 6 x 97909_Ans_Ans_pA076-085.qk_97909_Ans_Ans_pA076-085 10/7/10 2:32 PM Page 82 A82 APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES 41. (a) Inc on 共1, 兲; dec on 共, 1兲 (b) Loc min C共1兲 苷 3 (c) CU on 共, 0兲, 共2, 兲; CD on 共0, 2兲; 3 IP 共0, 0兲, (2, 6 s 2) (d) See graph at right. 43. (a) Inc on 共 , 2 兲; dec on 共0, 兲 (b) Loc min f 共 兲 苷 1 (c) CU on 共 兾3, 5 兾3兲; CD on 共0, 兾3兲, 共5 兾3, 2 兲; IP ( 兾3, 54 ), (5 兾3, 54 ) (d) See graph at right. 45. (a) VA x 苷 0; HA y 苷 1 (b) Inc on 共0, 2兲; dec on 共, 0兲, 共2, 兲 (c) Loc max f 共2兲 苷 54 (d) CU on 共3, 兲; CD on 共, 0兲, 共0, 3兲; IP (3, 119) (e) See graph at right. y { 2, 6 Œ„ 2} 0 _4 x (_1, _3) y 61. (a) The rate of increase is initially very small, increases to a maximum at t ⬇ 8 h, then decreases toward 0. (b) When t 苷 8 (c) CU on 共0, 8兲; CD on 共8, 18兲 (d) 共8, 350兲 63. K共3兲 K共2兲; CD 65. 28.57 min, when the rate of increase of drug level in the bloodstream is greatest; 85.71 min, when rate of decrease is greatest 1 67. f 共x兲 苷 9 共2x 3 3x 2 12x 7兲 69. (a) a 苷 0, b 苷 1 (b) y 苷 x at 共0, 0兲 EXERCISES 4.4 5π 5 π 5 ” 3, 4’ ” 3, 4’ 1 0 _1 2π ¨ π (π, _1) y y=1 (2, 5/4) 0 47. (a) HA y 苷 0 2 3 x x 0 y (b) Inc on 共, 0兲, dec on 共0, 兲 (c) Loc max f 共0兲 苷 1 (d) CU on (, 1s2 ), (1兾s2 , ); CD on (1兾s2 , 1兾s2 ); IP (1兾s2 , e 1兾2) (e) See graph at right. _1 0 1 (1, 0) 53. 共3, 兲 55. (a) Loc and abs max f 共1兲 苷 s2, no min (b) 1 4 (3 s17 ) 57. (b) CU on 共0.94, 2.57兲, 共3.71, 5.35兲; CD on 共0, 0.94兲, 共2.57, 3.71兲, 共5.35, 2 兲; IP 共0.94, 0.44兲, 共2.57, 0.63兲, 共3.71, 0.63兲, 共5.35, 0.44兲 59. CU on 共, 0.6兲, 共0.0, 兲; CD on 共0.6, 0.0兲 (2, 32) (4, 16) 0 3 3. A. ⺢ B. y-int 0; x-int 0, s 4 C. None D. None E. Inc on 共1, 兲; dec on 共, 1兲 F. Loc min f 共1兲 苷 3 G. CU on 共, 兲 H. See graph at right. x=e 0 y (6, 0) x x y x=0 1 PAGE 317 1. A. ⺢ B. y-int 0; x-int 0, 6 C. None D. None E. Inc on 共, 2兲, 共6, 兲; dec on 共2, 6兲 F. Loc max f 共2兲 苷 32; loc min f 共6兲 苷 0 G. CU on 共4, 兲; CD on 共, 4兲; IP 共4, 16兲 H. See graph at right. 1 49. (a) HA y 苷 0 N Abbreviation: int, intercept; SA, slant asymptote y Dec on 共, 兲 None CU on 共, 兲 See graph at right. 51. (a) VA x 苷 0, x 苷 e (b) Dec on 共0, e兲 (c) None (d) CU on (0, 1); CD on 共1, e兲; IP (1, 0) (e) See graph at right. PAGE 307 (b) 0 (c) 0 (d) , , or does not exist (e) Indeterminate 3. (a) (b) Indeterminate (c) 9 1 1 5. 4 7. 2 9. 3 11. 13. 2 15. 4 1 8 17. 0 19. 21. 5 23. 3 25. 2 27. 1 1 29. 1 31. 1兾 ln 3 33. 0 35. 1兾 2 37. 2 a共a 1兲 1 1 39. 24 41. 43. 3 45. 0 47. 2兾 49. 2 1 51. 2 53. 55. 1 57. e2 59. 1兾e 1 4 61. 1 63. e 65. 1兾se 67. e 2 69. 4 73. 1 75. f has an absolute minimum for c 0. As c increases, the minimum points get farther away from the origin. 1 81. 169 a 83. 2 85. 56 89. (a) 0 EXERCISES 4.5 (b) (c) (d) (e) N 1. (a) Indeterminate y 0 x (1, _3) x 5. A. ⺢ B. y-int 0; x-int 0, 4 C. None D. None E. Inc on 共1, 兲; dec on 共, 1兲 F. Loc min f 共1兲 苷 27 G. CU on 共, 2兲, 共4, 兲; CD on 共2, 4兲; IP 共2, 16兲, 共4, 0兲 H. See graph at right. y 0 (4, 0) x (2, _16) (1, _27) Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA076-085.qk_97909_Ans_Ans_pA076-085 10/7/10 2:32 PM Page 83 APPENDIX I 7. A. ⺢ B. y-int 0; x-int 0 C. About 共0, 0兲 D. None E. Inc on 共, 兲 F. None G. CU on 共2, 0兲, 共2, 兲; CD on 共, 2兲, 共0, 2兲; 256 IP (2, 256 15 ), 共0, 0兲, (2, 15 ) H. See graph at right. 19. A. ⺢ B. y-int 0; x-int 0 C. About y-axis D. HA y 苷 1 E. Inc on 共0, 兲; dec on 共, 0兲 F. Loc min f 共0兲 苷 0 G. CU on 共1, 1兲; CD on 共, 1兲, 共1, 兲; IP (1, 14 ) H. See graph at right. y {2, 256 15 } (0, 0) {_2, _ 256 15 } ⱍ 9. A. 兵x x 苷 1其 B. y-int 0; x-int 0 C. None D. VA x 苷 1, HA y 苷 1 E. Dec on 共, 1兲, 共1, 兲 F. None G. CU on 共1, 兲; CD on 共, 1兲 H. See graph at right. 11. A. 共, 1兲 傼 共1, 2兲 傼 共2, 兲 B. y-int 0; x-int 0 C. None D. HA y 苷 1; VA x 苷 2 E. Inc on 共, 1兲, 共1, 2兲, 共2, 兲 F. None G. CU on 共, 1兲, 共1, 2兲; CD on 共2, 兲 H. See graph at right. x y y1 x 0 x1 y (1, 1) 0 x 13. A. 兵x x 苷 3其 15. A. ⺢ B. y-int 0; x-int 0 C. About (0, 0) D. HA y 苷 0 E. Inc on 共3, 3兲; dec on 共, 3兲, 共3, 兲 F. Loc min f 共3兲 苷 16 ; loc max f 共3兲 苷 16 ; G. CU on (3 s3, 0), (3 s3, ); CD on (, 3 s3 ), (0, 3 s3 ); IP (0, 0), (3 s3, s3兾12) H. See graph at right. 17. A. 共, 0兲 傼 共0,兲 B. x-int 1 C. None D. HA y 苷 0; VA x 苷 0 E. Inc on 共0, 2兲; dec on 共, 0兲, 共2, 兲 F. Loc max f 共2兲 苷 14 G. CU on 共3, 兲; CD on 共, 0兲, 共0, 3兲; IP (3, 29 ) H. See graph at right. 1 4 1 4 ”1, ’ ”_1, ’ (0, 0) y 0 (1, _2) y y 1 ”3, 6 ’ x 1 ”_3, _ 6 ’ y 1 4 2 9 ”2, ’ ”3, ’ 0 1 x 0 _2 x 1 y y=1 (0, 0) x y=_1 ⱍⱍ ⱍ x3 x 3 27. A. { x x 1, x 苷 0} 苷 关1, 0兲 傼 共0, 1兴 B. x-int 1 C. About (0, 0) D. VA x 苷 0 E. Dec on 共1, 0兲, 共0, 1兲 1 F. None G. CU on (1, s2兾3 ), (0, s2兾3 ); CD on (s2兾3, 0), (s2兾3, 1); IP (s2兾3, 1兾s2 ) H. See graph at right. x x y B. x-int 2, 1 C. None D. None E. Inc on (1, ); dec on (, 2) F. None G. CD on 共, 2兲, 共1, 兲 H. See graph at right. 25. A. ⺢ B. y-int 0; x-int 0 C. About the origin D. HA y 苷 1 E. Inc on 共, 兲 F. None G. CU on 共, 0兲; CD on 共0, 兲; IP 共0, 0兲 H. See graph at right. ⱍ B. y-int 19 C. About y-axis D. VA x 苷 3, HA y 苷 0 E. Inc on 共, 3兲, 共3, 0兲; dec on (0, 3), 共3, 兲 F. Loc max f 共0兲 苷 19 G. CU on 共, 3兲, 共3, 兲; CD on 共3, 3兲 x 3 H. See graph at right. 21. A. 关0, 兲 B. y-int 0; x-int 0, 3 C. None D. None E. Inc on 共1, 兲; dec on 共0, 1兲 F. Loc min f 共1兲 苷 2 G. CU on 共0, 兲 H. See graph at right. A83 y=1 y 23. A. 共, 2兴 傼 关1, 兲 x=2 y=_1 ANSWERS TO ODD-NUMBERED EXERCISES y 1 x 0 29. A. ⺢ B. y-int 0; x-int 0, 3s3 C. About the origin D. None E. Inc on 共, 1兲, 共1, 兲; dec on 共1, 1兲 y F. Loc max f 共1兲 苷 2; 共_1, 2兲 loc min f 共1兲 苷 2 共3œ„3, 0兲 共0, 0兲 G. CU on 共0, 兲; CD on 共, 0兲; 0 x IP 共0, 0兲 共_3œ„ 3, 0兲 共1, _2兲 H. See graph at right. 31. A. ⺢ B. y-int 1; x-int 1 C. About y-axis D. None E. Inc on 共0, 兲; dec on 共, 0兲 F. Loc min f 共0兲 苷 1 G. CU on 共1, 1兲; CD on ; IP H. See graph at right. y (_1, 0) 0 (1, 0) (0, _1) Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. x 97909_Ans_Ans_pA076-085.qk_97909_Ans_Ans_pA076-085 10/7/10 2:32 PM Page 84 A84 APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES 33. A. ⺢ 43. A. ⺢ B. y-int 0; x-int n (n an integer) C. About 共0, 0兲, period 2 D. None E–G answers for 0 x : E. Inc on 共0, 兾2兲; dec on 共 兾2, 兲 F. Loc max f 共 兾2兲 苷 1 G. Let 苷 sin1s2兾3 ; CU on 共0, 兲, 共 , 兲; CD on 共 , 兲; IP at x 苷 0, , , H. y B. y-int. 12 C. None D. HA y 苷 0, y 苷 1 E. Inc on ⺢ F. None G. CU on 共, 0兲; CD on 共0, 兲; IP (0, 12 ) H. See graph at right. 45. A. 共0, 兲 B. None C. None D. VA x 苷 0 E. Inc on 共1, 兲; dec on 共0, 1兲 F. Loc min f 共1兲 苷 1 G. CU on 共0, 兲 H. See graph at right. x 2π y1 x 0 4π 0 _2π y y (1, 1) 0 兾2兲 B. y-int 0; x-int 0 C. About y-axis y D. VA x 苷 兾2 E. Inc on 共0, 兾2兲; π π dec on 共 兾2, 0兲 x 2 x 2 F. Loc min f 共0兲 苷 0 G. CU on 共 兾2, 兾2兲 H. See graph at right. x 0 x 35. A. 共 兾2, 47. A. ⺢ B. y-int 14 C. None D. HA y 苷 0, y 苷 1 E. Dec on ⺢ F. None G. CU on ; CD on 共, ln 12); IP (ln 12 , 49 ) H. See graph at right. 37. A. 共0, 3 兲 C. None D. None E. Inc on 共 兾3, 5 兾3兲, 共7 兾3, 3 兲; dec on 共0, 兾3兲, 共5 兾3, 7 兾3兲 F. Loc min f 共 兾3兲 苷 共 兾6兲 12 s3, f 共7 兾3兲 苷 共7 兾6兲 12 s3; y loc max f 共5 兾3兲 苷 共5 兾6兲 12 s3 G. CU on 共0, 兲, 共2 , 3 兲; CD on 共 , 2 兲; IP 共 , 兾2兲, 共2 , 兲 π 5π 7π 3 3 3 H. See graph at right. π 0 39. A. All reals except 共2n 1兲 2π 3π x _4π _3π _2π _π ”ln 12 , 49 ’ 0 π 2π 3π x 4π 0 (n an integer) 51. A. 共, 0兲 傼 共0, 兲 B. None C. None D. VA x 苷 0 E. Inc on 共, 1兲, 共0, 兲; dec on 共1, 0兲 F. Loc max f 共1兲 苷 e G. CU on 共0, 兲; CD on 共, 0兲 H. See graph at right. y 0 y=1 49. A. All x in 共2n , 共2n 1兲 兲 (n an integer) B. x-int 兾2 2n C. Period 2 D. VA x 苷 n E. Inc on 共2n , 兾2 2n 兲; dec on 共 兾2 2n , 共2n 1兲 兲 F. Loc max f 共 兾2 2n 兲 苷 0 G. CD on 共2n , 共2n 1兲 兲 H. y B. y-int 0; x-int 2n C. About the origin, period 2 D. VA x 苷 共2n 1兲 E. Inc on 共共2n 1兲 , 共2n 1兲 兲 F. None G. CU on 共2n , 共2n 1兲 兲; CD on 共共2n 1兲 , 2n 兲; IP 共2n , 0兲 H. x=_3π x=_π x=π x=3π _2π y 2π x y x (0 0) (_1, _e) x 53. A. ⺢ 41. A. ⺢ B. y-int 兾4 C. None D. HA y 苷 0, y 苷 兾2 E. Inc on 共, 兲 F. None G. CU on 共, 0兲; CD on 共0, 兲; IP 共0, 兾4兲 H. See graph at right. y B. y-int 2 C. None D. None E. Inc on ( 15 ln 23, ); dec on (, 15 ln 23 ) y=π/2 F. Loc min f ( 15 ln 23) 苷 G. CU on 共, 兲 H. See graph at right. (0, π/4) 0 y=0 y ( 23) 3兾5 ( 23) 2兾5 local minimum (0, 2) x 0 x Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA076-085.qk_97909_Ans_Ans_pA076-085 10/7/10 2:32 PM Page 85 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 55. 71. m A85 y π yx2 (0, m¸) √=c 0 √ x 0 yx π 2 75. VA x 苷 0, asymptotic to y 苷 x 3 57. (a) When t 苷 共ln a兲兾k (c) (b) When t 苷 共ln a兲兾k y y 10 ƒ 1 y=˛ 2 1/2 0 0 EXERCISES 4.6 59. N PAGE 324 1. Inc on 共0.92, 2.5兲, 共2.58, 兲; dec on , 共2.5, 2.58兲; y 0 x 10 x ln a k 2 L/2 L loc max f 共2.5兲 苷 4; loc min f 共0.92兲 ⬇ 5.12, f 共2.58兲 ⬇ 3.998; CU on 共, 1.46兲, 共2.54, 兲; CD on 共1.46, 2.54兲; IP 共1.46, 1.40兲, 共2.54, 3.999兲 x 10 61. y 苷 x 1 4.04 63. y 苷 2 x 2 ƒ 65. A. 共, 1兲 傼 共1, 兲 y B. y-int 0; x-int 0 C. None D. VA x 苷 1; SA y 苷 x 1 E. Inc on 共, 0兲, 共2, 兲; dec on 共0, 1兲, 共1, 2兲 F. Loc max f 共0兲 苷 0; loc min f 共2兲 苷 4 G. CU on 共1, 兲; CD on 共, 1兲 H. See graph at right. 67. A. 共, 0兲 傼 共0, 兲 3 B. x-int s C. None 4 D. VA x 苷 0; SA y 苷 x E. Inc. on 共, 0兲, 共2, 兲; dec on 共0, 2兲 F. Loc min f 共2兲 苷 3 G. CU on 共, 0兲, 共0, 兲 H. See graph at right. 69. A. ⺢ B. y-int 2 C. None D. SA y 苷 1 12 x E. Inc. on 共ln 2, 兲; dec on 共, ln 2兲 F. Loc min f 共ln 2兲 苷 32 12 ln 2 G. CU on 共, 兲 H. See graph at right. 0 (2, 4) 2.4 _6 x (0, 0) ƒ 4 2.7 3.96 3. Inc on 共15, 4.40兲, 共18.93, 兲; dec on 共, 15兲, 共4.40, 18.93兲; loc max f 共4.40兲 ⬇ 53,800; loc min f 共15兲 ⬇ 9,700,000, f 共18.93兲 ⬇ 12,700,000; CU on 共, 11.34兲, 共0, 2.92兲, 共15.08, 兲; CD on 共11.34, 0兲, 共2.92, 15.08兲; IP 共0, 0兲, ⬇ 共11.34, 6,250,000兲, 共2.92, 31,800兲, 共15.08, 8,150,000兲 y 10,000,000 y=x (2, 3) 60,000 f f _25 25 _10 _2 0 10 x _13,000,000 _30,000 5. Inc on 共, 1.47兲, 共1.47, 0.66兲; dec on 共0.66, 兲; loc max f 共0.66兲 ⬇ 0.38; CU on 共, 1.47兲, 共0.49, 0兲, 共1.10, 兲; CD on 共1.47, 0.49兲, 共0, 1.10兲; IP 共0.49, 0.44兲, 共1.10, 0.31兲 y {ln 2, 32 + 21 ln 2} 2 3 f 1 2 1 y=1+ x 0 1 _4 x 3 xÅ_1.47 _3 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA086-095.qk_97909_Ans_Ans_pA086-095 10/7/10 2:36 PM Page 86 A86 APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES 7. Inc on 共1.40, 0.44兲, 共0.44, 1.40兲; dec on 共, 1.40兲, 17. Inc on 共9.41, 1.29兲, 共0, 1.05兲; dec on 共, 9.41兲, 共0.44, 0兲, 共0, 0.44兲, 共1.40, 兲; loc max f 共0.44兲 ⬇ 4.68, f 共1.40兲 ⬇ 6.09; loc min f 共1.40兲 ⬇ 6.09, f 共0.44兲 ⬇ 5.22; CU on 共, 0.77兲, 共0, 0.77兲; CD on 共0.77, 0兲, 共0.77, 兲; IP 共0.77, 5.22兲, 共0.77, 5.22兲 共1.29, 0兲, 共1.05, 兲; loc max f 共1.29兲 ⬇ 7.49, f 共1.05兲 ⬇ 2.35; loc min f 共9.41兲 ⬇ 0.056, f 共0兲 苷 0.5; CU on 共13.81, 1.55兲, 共1.03, 0.60兲, 共1.48, 兲; CD on 共, 13.81兲, 共1.55, 1.03兲, 共0.60, 1.48兲; IP 共13.81, 0.05兲, 共1.55, 5.64兲, 共1.03, 5.39兲, 共0.60, 1.52兲, 共1.48, 1.93兲 8 f 8 _π 1 f π _8 9. Inc on (8 s61, 8 s61 ); dec on (, 8 s61 ), f _6 6 _15 0 _1 _0.1 共8 s61, 0兲, 共0, 兲; CU on (12 s138, 12 s138 ), 19. Inc on 共4.91, 4.51兲, 共0, 1.77兲, 共4.91, 8.06兲, 共10.79, 14.34兲, 共0, 兲; CD on (, 12 s138 ), (12 s138, 0) 75 1 f f _1 _100 1 _1 0.95 11. (a) _10 1 共17.08, 20兲; dec on 共4.51, 4.10兲, 共1.77, 4.10兲, 共8.06, 10.79兲, 共14.34, 17.08兲; loc max f 共4.51兲 ⬇ 0.62, f 共1.77兲 ⬇ 2.58, , f 共14.34兲 ⬇ 4.39; loc min f 共10.79兲 ⬇ 2.43, f 共17.08兲 ⬇ 3.49; CU on 共9.60, 12.25兲, 共15.81, 18.65兲; CD on 共4.91, 4.10兲, 共0, 4.10兲, 共4.91, 9.60兲, 共12.25, 15.81兲, 共18.65, 20兲; IP at 共9.60, 2.95兲, 共12.25, 3.27兲, 共15.81, 3.91兲, 共18.65, 4.20兲 5 冢 œ„1e , 2e 冣 1 f 1.75 _0.25 _0.25 _5 (b) limx l 0 f 共x兲 苷 0 (c) Loc min f (1兾se ) 苷 1兾共2e兲; CD on 共0, e3兾2 兲; CU on 共e3兾2, 兲 13. Loc max f 共5.6兲 ⬇ 0.018, f 共0.82兲 ⬇ 281.5, f 共5.2兲 ⬇ 0.0145; loc min f 共3兲 苷 0 y 21. Inc on 共, 0兲, 共0, 兲; CU on 共, 0.42兲, 共0, 0.42兲; CD on 共0.42, 0兲, 共0.42, 兲; IP 共 0.42, 0.83兲 0.02 8 1 20 0 1 ƒ _3 3 ƒ 3.5 _1 x 500 0.01 0.6 23. 0.04 0.03 1 2 _2 2.5 1500 f 共x兲 苷 2 8 25. (a) 2 2 0 3 2 x 共x 1兲 共x 18x 44x 16兲 共x 2兲3共x 4兲5 2 15. f 共x兲 苷 0 0 3 2 共x 1兲共x 6 36x 5 6x 4 628x 3 684x 2 672x 64兲 共x 2兲4共x 4兲6 CU on 共35.3, 5.0兲, 共1, 0.5兲, 共0.1, 2兲, 共2, 4兲, 共4, 兲; CD on 共, 35.3兲, 共5.0, 1兲, 共0.5, 0.1兲; IP 共35.3, 0.015兲, 共5.0, 0.005兲, 共1, 0兲, 共0.5, 0.00001兲, 共0.1, 0.0000066兲 0 8 _1 (b) lim x l0 x 1兾x 苷 0, lim x l x 1兾x 苷 1 (c) Loc max f 共e兲 苷 e 1兾e (d) IP at x ⬇ 0.58, 4.37 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA086-095.qk_97909_Ans_Ans_pA086-095 10/7/10 2:36 PM Page 87 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 27. Max f 共0.59兲 ⬇ 1, f 共0.68兲 ⬇ 1, f 共1.96兲 ⬇ 1; min f 共0.64兲 ⬇ 0.99996, f 共1.46兲 ⬇ 0.49, f 共2.73兲 ⬇ 0.51; IP 共0.61, 0.99998兲, 共0.66, 0.99998兲, 共1.17, 0.72兲, 共1.75, 0.77兲, 共2.28, 0.34兲 ⱍ ⱍ 35. For c 1, the graph has loc max and min values; for 1 it does not. The function increases for c 1 and decreases for c 1. As c changes, the IPs move vertically but not horizontally. ⱍcⱍ 10 c=3 c=1 1.2 c=0.5 c=0 f 0 _15 π 1 5 c=_0.5 1.2 _10 c=_3 c=_1 37. 1.2 1 3 f f _2π 1 _2 0 2π 3 _3 0.55 0.9997 0.73 _1.2 29. For c 0, there is an absolute minimum at the origin. There are no other maxima or minima. The more negative c becomes, the farther the two IPs move from the origin. c 苷 0 is a transitional value. 10 c=4 2 1 _3 For c 0, lim x l f 共x兲 苷 0 and lim x l f 共x兲 苷 . For c 0, lim x l f 共x兲 苷 and lim x l f 共x兲 苷 0. As c increases, the max and min points and the IPs get closer to the origin. 39. (a) Positive (b) c=4 ⱍ ⱍ c=1 c=0.5 c=0.2 c=0.1 12 c=_4 _4 4 c=0 0 31. For c 0, there is no extreme point and one IP, which decreases along the x-axis. For c 0, there is no IP, and one minimum point. c=5 _6 6 c=0 10 _12 1 c= 5 _10 c=0 10 EXERCISES 4.7 c=_5 1 c=_ 5 N _10 3. 10, 10 33. For c 5. 9 4 12,500 ft@ 50 0, the maximum and minimum values are always 1 2 , but the extreme points and IPs move closer to the y-axis as c increases. c 苷 0 is a transitional value: when c is replaced by c, the curve is reflected in the x-axis. c=_1 c=_4 PAGE 331 1. (a) 11, 12 (b) 11.5, 11.5 7. 25 m by 25 m 9. N 苷 1 11. (a) 250 12,500 ft@ 100 9000 ft@ 120 0.6 0.2 0.5 1 2 5 4 5 1 0.6 A87 125 75 (b) x y Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA086-095.qk_97909_Ans_Ans_pA086-095 10/7/10 2:36 PM Page 88 A88 APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES (c) A 苷 xy (d) 5x 2y 苷 750 (e) A共x兲 苷 375x 52 x 2 2 (f) 14,062.5 ft 13. 1000 ft by 1500 ft 15. 4000 cm3 17. $191.28 6 3 1 4 19. (5 , 5) 21. (3 , 3 s2 ) 23. Square, side s2 r 25. L兾2, s3 L兾4 27. Base s3 r, height 3r兾2 29. 4r 3兾(3 s3 ) 31. r 2(1 s5 ) 33. 24 cm, 36 cm 35. (a) Use all of the wire for the square (b) 40 s3兾(9 4 s3 ) m for the square 3 37. Height 苷 radius 苷 s V兾 cm 3 39. V 苷 2R 兾(9 s3 ) 43. E 2兾共4r兲 3 2 45. (a) 2 s csc 共csc s3 cot 兲 (b) cos1(1兾s3 ) ⬇ 55 (c) 6s[h s兾(2 s2 )] 47. Row directly to B 49. ⬇ 4.85 km east of the refinery 3 3 51. 10 s 3兾(1 s 3 ) ft from the stronger source 53. 共a 2兾3 b 2兾3 兲3兾2 55. 2s6 57. (b) (i) $342,491; $342兾unit; $390兾unit (ii) 400 (iii) $320兾unit 1 59. (a) p共x兲 苷 19 3000 x (b) $9.50 1 61. (a) p共x兲 苷 550 10 x (b) $175 (c) $100 65. 9.35 m 69. x 苷 6 in. 71. 兾6 1 73. At a distance 5 2 s5 from A 75. 2 共L W 兲2 77. (a) About 5.1 km from B (b) C is close to B; C is close to D; W兾L 苷 s25 x 2兾x, where x 苷 BC (c) ⬇1.07 ; no such value (d) s41兾4 ⬇ 1.6 ⱍ EXERCISES 4.8 N ⱍ PAGE 342 1. (a) x2 ⬇ 2.3, x3 ⬇ 3 (b) No 9 3. 2 5. a, b, c 7. 1.1785 9. 1.25 11. 1.82056420 13. 1.217562 15. 1.964636 17. 3.637958, 1.862365, 0.889470 19. 1.412391, 3.057104 21. 0, 0.902025 23. 1.93822883, 1.21997997, 1.13929375, 2.98984102 25. 0.76682579 27. 0.21916368, 1.08422462 29. (b) 31.622777 35. (a) 1.293227, 0.441731, 0.507854 (b) 2.0212 37. 共1.520092, 2.306964兲 39. 共0.410245, 0.347810兲 41. 0.76286% EXERCISES 4.9 N PAGE 348 1. F 共x兲 苷 x 3x C 3. F 共x兲 苷 2 x 4 x 3 5 x 4 C 1 2 3 5. F 共x兲 苷 x 2 x x C 7. F 共x兲 苷 5x 7兾5 40x 1兾5 C 3 9. F 共x兲 苷 s2 x C 11. F 共x兲 苷 2x 3兾2 2 x 4兾3 C 1 2 2 3 13. F 共x兲 苷 1 2 再 1 5 1 5 ⱍ ⱍ ⱍ ⱍ x 2 ln x C1 if x x 2 ln x C2 if x 1 1 37. 2 x 2兾3 2 if x 3 0 39. x 2x x 12x 4 41. sin cos 5 4 1 43. f 共x兲 苷 2x 2 x 3 2x 4 2x 3 45. x 2 cos x 2 x 47. ln x 共ln 2兲x ln 2 49. 10 51. b 2 53. ⱍ ⱍ 23. F共x兲 苷 x 5 3 x 6 4 1 4 y F 0 x 1 55. 57. y y (2, 2) 2 1 (1, 1) 0 1 F (3, 1) 2 _2π 0 2π x x 3 _1 59. 61. 63. 65. (c) 69. 75. 79. (d) s共t兲 苷 1 cos t sin t s共t兲 苷 13 t 3 12 t 2 2t 3 s共t兲 苷 10 sin t 3 cos t 共6兾兲t 3 (a) s共t兲 苷 450 4.9t 2 (b) s450兾4.9 ⬇ 9.58 s 9.8s450兾4.9 ⬇ 93.9 m兾s (d) About 9.09 s 130 225 ft 71. $742.08 73. 11 ⬇ 11.8 s 88 2 77. 62,500 km兾h2 ⬇ 4.82 m兾s2 15 ⬇ 5.87 ft兾s (a) 22.9125 mi (b) 21.675 mi (c) 30 min 33 s 55.425 mi CHAPTER 4 REVIEW N PAGE 351 True-False Quiz 1. False 11. True 3. False 13. False 5. True 15. True 7. False 9. True 17. True 19. True Exercises 1. Abs max f 共4兲 苷 5, abs and loc min f 共3兲 苷 1 2 1 9 3. Abs max f 共2兲 苷 5, abs and loc min f (3 ) 苷 2 5. Abs and loc max f 共兾6兲 苷 兾6 s3 , abs min f 共2兲 苷 2, loc min f 共5兾6兲 苷 5兾6 s3 1 7. 1 9. 8 11. 0 13. 2 15. 0 0 y x6 2 0 1 2 5兾2 5 n an integer 19. F 共x兲 苷 5e x 3 sinh x C 1 21. F 共x兲 苷 2 x 2 ln x 1兾x 2 C 3 1 15. G共t兲 苷 2t t t C 17. H共 兲 苷 2 cos tan Cn on 共n 兾2, n 兾2兲, 2 3兾2 3 1兾2 0; 32 x 2兾3 52 if x 1 17. 9 x 12 y y=2 25. f 共x兲 苷 x 5 x 4 x 3 Cx D 27. x 8兾3 Cx D 29. f 共t兲 苷 sin t Ct 2 Dt E 31. f 共x兲 苷 x 2x 3兾2 5 33. f 共t兲 苷 4 arctan t 3 20 x y=_2 35. 2 sin t tan t 4 2s3 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA086-095.qk_97909_Ans_Ans_pA086-095 10/7/10 2:36 PM Page 89 APPENDIX I 19. A. ⺢ B. y-int 2 C. None D. None E. Dec on 共, 兲 F. None G. CU on 共, 0兲; CD on 共0, 兲; IP 共0, 2兲 H. See graph at right. 31. A. 2 x y 2 1 0 1 ⱍ 23. A. 兵x x 苷 0, 3其 B. None C. None D. HA y 苷 0; VA x 苷 0, x 苷 3 E. Inc on 共1, 3兲; dec on 共, 0兲, 共0, 1兲, 共3, 兲 F. Loc min f 共1兲 苷 14 G. CU on 共0, 3兲, 共3, 兲; CD on 共, 0兲 H. See graph at right. x 2 y 0 x x3 ⱍ 25. A. 兵x x 苷 8其 y B. y-int 0, x-int 0 C. None D. VA x 苷 8; SA y 苷 x 8 E. Inc on 共, 16兲, 共0, 兲; dec on 共16, 8兲, 共8, 0兲 F. Loc max f 共16兲 苷 32; loc min f 共0兲 苷 0 G. CU on 共8, 兲; CD on 共, 8兲 H. See graph at right. x 8 0 共16, 32兲 x y x 8 x 1 _ π 2 y {3, e_#} 1 0 x 2 _2 1.5 ƒ _5 5 _1.5 2.5 f 2.1 _0.5 _20 x 4 ”_ 3 , _ } e# π/4 π _1 0 y _π/4 0 π 2 37. Inc on 共0.23, 0兲, 共1.62, 兲; dec on 共, 0.23兲, 共0, 1.62兲; loc max f 共0兲 苷 2; loc min f 共0.23兲 ⬇ 1.96, f 共1.62兲 ⬇ 19.2; CU on 共, 0.12兲, 共1.24, 兲; CD on 共0.12, 1.24兲; IP 共0.12, 1.98兲, 共1.24, 12.1兲 _1 {_π4 , _ œ„22 e } _π 35. Inc on (s3, 0), (0, s3 ); dec on (, s3 ), (s3, ); loc max f (s3 ) 苷 29 s3, loc min f (s3 ) 苷 29 s3; CU on (s6, 0), (s6, ); CD on (, s6 ), (0, s6 ); IP (s6, 365 s6 ), (s6, 365 s6 ) f 4œ„ 6 ’ 9 29. A. 关, 兴 B. y-int 0; x-int , 0, C. None D. None E. Inc on (兾4, 3兾4 ); dec on (, 兾4 ), (3兾4, ) F. Loc max f 共3兾4兲 苷 12 s2 e 3兾4, loc min f 共兾4兲 苷 12 s2 e 3兾4 G. CU on 共兾2, 兾2兲; CD on 共, 兾2兲, 共兾2, 兲; IP 共兾2, e兾2 兲, 共兾2, e 兾2 兲 H. y 3π œ„2 2 33. A. ⺢ B. y-int 2; x-int 2 C. None D. HA y 苷 0 E. Inc on 共, 3兲; dec on 共3, 兲 F. Loc max f 共3兲 苷 e3 G. CU on 共4, 兲; CD on 共, 4兲; IP 共4, 2e4 兲 H. See graph at right. A89 y 15 27. A. 关2, 兲 B. y-int 0; x-int 2, 0 C. None D. None E. Inc on ( 43 , ), dec on (2, 43 ) F. Loc min f ( 43 ) 苷 49 s6 G. CU on 共2, 兲 H. See graph at right. {4, {x ⱍ ⱍ x ⱍ 1} B. None C. About (0, 0) D. HA y 苷 0 E. Dec on 共, 1兲, 共1, 兲 F. None G. CU on 共1, 兲; CD on 共, 1兲 H. See graph at right. y 21. A. ⺢ B. y-int 0; x-int 0, 1 C. None D. None E. Inc on ( 14 , ), dec on (, 14 ) 27 F. Loc min f ( 14 ) 苷 256 1 G. CU on (, 2 ), 共1, 兲; CD on ( 12 , 1); IP ( 12 , 161 ), 共1, 0兲 H. See graph at right. ANSWERS TO ODD-NUMBERED EXERCISES x 39. 0.4 共 0.82, 0.22兲; ( s2兾3, e3兾2 ) 1 _5 1.5 5 0 41. 2.96, 0.18, 3.01; 1.57, 1.57; 2.16, 0.75, 0.46, 2.21 43. For C 1, f is periodic with period 2 and has local maxima at 2n 兾2, n an integer. For C 1, f has no graph. For 1 C 1, f has vertical asymptotes. For C 1, f is continuous on ⺢. As C increases, f moves upward and its oscillations become less pronounced. 49. (a) 0 (b) CU on ⺢ 53. 3 s3 r 2 57. L 苷 C 59. $11.50 55. 4兾s3 cm from D 61. 1.297383 63. 1.16718557 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA086-095.qk_97909_Ans_Ans_pA086-095 10/7/10 2:36 PM Page 90 A90 APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES 65. f 共x兲 苷 sin x sin1x C 67. f 共x兲 苷 x 2 5 5兾2 x 3 5 5兾3 5. (a) 8, 6.875 C (b) 5, 5.375 y y 2 2 y y 69. f 共t兲 苷 t 2 3 cos t 2 71. f (x兲 苷 2 x 2 x 3 4x 4 2x 1 1 73. s共t兲 苷 t 2 tan1 t 1 2 2 75. (b) 0.1e x cos x 0.9 (c) 5 0 1 x 0 0 x 1 0 x 1 1 x F (c) 5.75, 5.9375 _4 y y 2 2 4 _1 77. No 79. (b) About 8.5 in. by 2 in. 83. (a) 20 s2 ⬇ 28 ft (c) 20兾s3 in., 20 s2兾3 in. 0 dI 480k共h 4兲 (b) , where k is the constant 苷 dt 关共h 4兲2 1600兴 5兾2 of proportionality 1 0 x 1 x (d) M6 7. n 苷 2: upper 苷 3 ⬇ 9.42, lower 苷 2 ⬇ 6.28 y 3 PROBLEMS PLUS N PAGE 356 3. Abs max f 共5兲 苷 e 45, no abs min 7. 24 9. 共2, 4兲, 共2, 4兲 13. 共m兾2, m 2兾4兲 15. a 2 e 1兾e 19. (a) T1 苷 D兾c1, T2 苷 共2h sec 兲兾c1 共D 2h tan 兲兾c2, T3 苷 s4h 2 D 2兾c1 (c) c1 ⬇ 3.85 km兾s, c2 ⬇ 7.66 km兾s, h ⬇ 0.42 km 3 23. 3兾(s 2 1) ⬇ 1112 h 1 0 π x 3π 4 π x 3π 4 π x π 2 n 苷 4: upper 苷 (10 s2 )共兾4兲 ⬇ 8.96, lower 苷 (8 s2 )共兾4兲 ⬇ 7.39 y 3 CHAPTER 5 2 EXERCISES 5.1 N PAGE 369 1 1. (a) L 4 苷 33, R 4 苷 41 y 6 y 6 4 4 2 2 0 π 4 π 2 n 苷 8: upper ⬇ 8.65, lower ⬇ 7.86 y 0 2 4 6 8x 0 2 4 6 3 8x (b) L8 ⬇ 35.2, R8 ⬇ 39.2 3. (a) 0.7908, underestimate 2 (b) 1.1835, overestimate y y 1 1 1 0 0 ƒ=cos x π 8 π 4 3π 8 π 2 x 0 ƒ=cos x π 8 π 4 3π 8 π 2 x π 4 π 2 9. 0.2533, 0.2170, 0.2101, 0.2050; 0.2 11. (a) Left: 0.8100, 0.7937, 0.7904; right: 0.7600, 0.7770, 0.7804 13. 34.7 ft, 44.8 ft 15. 63.2 L, 70 L 17. 155 ft Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA086-095.qk_97909_Ans_Ans_pA086-095 10/7/10 2:36 PM Page 91 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I n 2共1 2i兾n兲 2 21. lim 兺 ssin共 i兾n兲 ⴢ ⴢ 2 n l i苷1 共1 2i兾n兲 1 n l i苷1 n n 23. The region under the graph of y 苷 tan x from 0 to 兾4 25. (a) L n A Rn n 19. lim 兺 27. (a) lim nl n 2共n 1兲2共2n 2 2n 1兲 12 n 64 n6 兺i 5 (b) i苷1 (c) 32 3 EXERCISES 5.3 N A91 PAGE 394 1. One process undoes what the other one does. See the Fundamental Theorem of Calculus, page 393. 3. (a) 0, 2, 5, 7, 3 (d) y (b) (0, 3) (c) x 苷 3 g 29. sin b, 1 EXERCISES 5.2 1 PAGE 382 N 0 1. 6 y 3 ƒ=3- 1 x 2 The Riemann sum represents the sum of the areas of the two 2 1 rectangles above the x-axis minus the sum of the areas of 0 2 the three rectangles below the x-axis; that is, the net area of the rectangles with respect to the x-axis. 3. 2.322986 The Riemann sum represents the sum of the areas of the three rectangles above the x-axis minus the area of the rectangle below the x-axis. 5. y=t@ x 6 0 6 11. F共x兲 苷 s1 sec x 3 15. y 苷 stan x stan x sec2 x 17. y 苷 1 2 5. (a) 6 (b) 4 (c) 2 7. Lower, L 5 苷 64; upper, R5 苷 16 17. 6 2 x 5 10 50 100 1.933766 1.983524 1.999342 1.999836 x ln共1 x 兲 dx 2 21. 9 23. 29. lim 兺 n l i苷1 n 31. lim 兺 n l i苷1 45. e e 3 47. E 59. 3 x14 sx dx 63. 0 y 0 A x xe 41. e 2 1 43. 0 39. 5 1 x D dx 40 3 1 e1 e1 23. 31. 1 52 3 33. 49 3 39. 4兾3 关2, 1兴, so FTC2 cannot be applied. 47. The function f 共 兲 苷 sec tan is not continuous on the interval 关兾3, 兴, so FTC2 cannot be applied. 243 49. 4 51. 2 53. 3.75 y=˛ 1 0 (d) 2 5 2 41. 0 61. 12 71. 55. t共x兲 苷 43. 3 兾3 y 兾4 1 0 x 4 x dx s3 12 tan x dx 73. 1 2 2 x 2共4x 2 1兲 3共9x 2 1兲 2 4x 1 9x 2 1 4 49. 122 53. 15 C 2兾e 29. 21. 63 共5x 4x兲 dx f 共x兲 dx 6 3 4 3 冊 51. B 2 x 19. 9 5 37 37. 3 4 冉 27. 6 35. ln 2 7 25. 2 3 37. 3 4 3 2 25. 1 s3兾2 19. y 7 2 5 i 2 sin 苷 n n 5 (b) 10 (c) 3 33. (a) 4 35. The values of Rn appear to be approaching 2. 2 4i兾n 4 ⴢ 1 共2 4i兾n兲5 n n x 3共1 3x兲3 1 共1 3x兲2 13. h共x兲 苷 xe x 45. The function f 共x兲 苷 x 4 is not continuous on the interval 13. 0.9029, 0.9018 Rn 9. t共s兲 苷 共s s 2 兲8 4 0 _1 n t x 7. t共x兲 苷 1兾共x 3 1兲 ƒ=´-2 5 1 11. 0.9071 1 y 2 9. 6.1820 15. (a), (b) x 2 y 8 10 12 14 4 x 1 2 57. F共x兲 苷 2xe x e x 59. y 苷 sin x ln共1 2 cos x兲 cos x ln共1 2 sin x兲 61. 共4, 0兲 63. 29 65. (a) 2 sn, s4n 2, n an integer 0 (b) 共0, 1兲, (s4n 1, s4n 3 ), and (s4n 1, s4n 1 ), (c) 0.74 n an integer 0 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA086-095.qk_97909_Ans_Ans_pA086-095 10/7/10 2:36 PM Page 92 A92 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 67. (a) Loc max at 1 and 5; y loc min at 3 and 7 (b) x 苷 9 1 2 0 (d) See graph at right. _1 4 6 8 x ⱍ ⱍ 43. ln sin1 x C 1 40 47. 1 3 37. 39. ln共1 cos 2 x兲 C 2 ( 12 , 2), 共4, 6兲, 共8, 9兲 (c) 35. 3 共cot x兲3兾2 C sinh3x C ⱍ _2 1 共2x 5兲10 36 共2x 5兲 9 C 5 49. 共x 1兲 C 1 8 2 51. e cos x C 4 2 1 69. 77. f 共x兲 苷 x 3兾2, a 苷 9 79. (b) Average expenditure over 关0, t兴; minimize average 1 4 expenditure ⱍ 41. ln sin x C 45. tan1x 2 ln共1 x 2 兲 C f F 0 _2 2π 2 F f EXERCISES 5.4 N PAGE 403 5. x 共1兾x兲 C 1 3 2 3 7. x x x 2x C 1 4 8 1 3 11. 3 1 15. 2 2 5 9. u 3 2 u 2 4u C 1 8 2 x 4 sx C 9 10 5 53. 2兾 55. 63. 3 csc C 13. cos x cosh x C 17. tan C 1 19. sin x 4 x 2 C 20 _3 _1 1 5 3 65. 1 3 45 28 冉 1. True 11. False _6 55 63 31. 39. 256 5 27. 5e 1 25. 2 21 5 29. 36 1 9 33. 2 ln 2 35. 11 ln 10 41. 兾3 43. 兾6 45. 3.5 37. 1 兾4 3 4 47. ⬇1.36 PAGE 416 3. True 13. True 5. False 15. False 1. (a) 8 7. True 9. True 17. False (b) 5.7 y y=ƒ 2 ages of 5 and 10 1000 to 5000 units 3 57. Newton-meters 59. (a) 2 m (b) 416 m 1 61. (a) v共t兲 苷 2 t 2 4t 5 m兾s (b) 416 23 m 2 63. 46 3 kg 65. 1.4 mi 67. $58,000 19. 2 1 1 2 1 3 sin 1 5. 4 cos 4 C 1 9. 20 共1 2x兲10 C 1 13. 76 21. 0 25. sx 4x C ⱍ ⱍ 29. 2e sx C 1 4 ln共1 x 4 兲 C 13. 3 ln 5 3x C 33. 15. (1兾兲 cos t C 1 C 1 eu 1 21. 3 共ln x兲3 C 39. 2 s1 sin x C 19. 3 s3ax bx 3 C 2 25. 3 共1 e x 兲3兾2 C 2 1 cos共5 t 兲 C ln 5 1 17. 27. 1 15 23. 1 4 tan4 C 31. e tan x C 33. 45. t共x兲 苷 4x 3 cos共x 8 兲 49. 4 共x 3 3x兲 5 C 1 C sin x 15. 21 4 17. Does not exist ⱍ ⱍ 23. 共1兾x兲 2 ln x x C 1 sin 2 t C 27. 2 31. 2 关ln共cos x兲兴 2 C 11. 3 共2x x 2 兲 3兾2 C 1 x 2 7. f is c, f is b, x0x f 共t兲 dt is a 5. 3 9 10 2 3. 9 共x 3 1兲3兾2 C 7. 2 cos共x 2 兲 C 6 0 x 2 兾4 9. 37 11. PAGE 413 y=ƒ 2 6 0 3. 71. 4.75 10 5 megawatt-hours 69. 5443 bacteria 29. 91. 2兾4 85. 5 Exercises 53. Number of gallons of oil leaked in the first 2 hours 55. Increase in revenue when production is increased from 1. e x C N L y 51. The increase in the child’s weight (in pounds) between the N 61. 0 69. 2 4 3 49. EXERCISES 5.5 16 15 1 3 True-False Quiz 10 23. 冊 5 2 t 1 cos 4 5 83. 0 CHAPTER 5 REVIEW 21. 103 67. 71. ln共e 1兲 73. 16 75. s3 77. 6 79. All three areas are equal. 81. ⬇ 4512 L _5 _10 59. e se 57. 4 (2 s2 1) a 3 x13 sx 2 3 dx 1 ⱍ ⱍ 35. ln 1 sec C 41. 64 5 37. 23 3 43. F共x兲 苷 x 2兾共1 x 3 兲 47. y 苷 (2e x e sx )兾共2x兲 4 s3 55. 0.280981 57. Number of barrels of oil consumed from Jan. 1, 2000, through Jan. 1, 2008 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA086-095.qk_97909_Ans_Ans_pA086-095 10/7/10 2:36 PM Page 93 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 59. 72,400 61. 3 63. c ⬇ 1.62 2 65. e 2x共2x 1兲兾共1 ex 兲 71. 3 PROBLEMS PLUS 1. 兾2 7. 4 兾21 y y (1, 1) PAGE 420 N y=x 9. 关1, 2兴 7. e2 5. 1 3. 2k A93 y=˛ 11. (a) 2 共n 1兲n 1 0 0 x x (b) 12 冀b冁共2b 冀b冁 1兲 12 冀a冁共2a 冀a冁 1兲 17. 2(s2 1) CHAPTER 6 EXERCISES 6.1 1. N 3. e 共1兾e兲 32 3 9. ln 2 1 2 19. 2兾 9. 64兾15 PAGE 427 8 3 11. 5. e 共1兾e兲 10 3 23. 1 2 5 2 17. 25. 31. 2 s3 1 33. 0, 0.90; 0.04 35. 1.11, 1.25, 2.86; 8.38 37. 2.80123 29. 7. 15. e 2 13. 72 21. 2 2 ln 2 2 3 4 3 59 12 y y ¥=x 9 2 32 3 (4, 2) x=2y 27. ln 2 x 0 x 0 3 41. 12s6 9 1 39. 0.25142 11. 11兾30 45. 4232 cm2 43. 117 3 ft y y y=≈ 47. (a) Car A (b) The distance by which A is ahead of B after 1 minute (c) Car A (d) t ⬇ 2.2 min 24 49. 5 s3 51. 4 2兾3 53. 6 55. 0 m 1; m ln m 1 2 y=1 y=1 0 0 x 1 x 1 x=y@ EXERCISES 6.2 1. 19兾12 N PAGE 438 y y 1 y=2- 2 x 13. 2 ( 3 s3 ) 4 y 1 π x=1 ”_ 3 , 3’ x=2 1 y=0 2 0 y=3 y π ” 3 , 3’ y=1+sec x x 0 x y=1 0 3. 8 x 0 x y y x-1 y=œ„„„„ 15. 3兾5 x=5 0 y=1 1 5 y=0 x 0 x y y=x# 1 5. 162 y 0 y x 1 x=2 y=9 (6, 9) y x=0 1 x=2œ„ y 0 x 0 x 0 1 3 4 x x=2 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA086-095.qk_97909_Ans_Ans_pA086-095 10/7/10 2:36 PM Page 94 A94 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 17. 10s2 兾3 33. 0.13 y 43. 117兾5 x=3 { 21 , œ„21 } x=¥ 9. (a) y x=3 0 N 25 24 29. 17兾45 EXERCISES 6.5 1 2x 2 0 2x 2 31. (a) 2 x e dx ⬇ 3.75825 2 2ex ) dx ⬇ 13.14312 (b) 2 x01 (e 47. r h 11. W2 苷 3W1 (b) 10.8 cm (b) 1875 4 ft-lb 冉 冊 23. 兾3 27. 兾3 41. 4兾3 2 PAGE 449 ⬇ 1.04 J 1 1 a b 29. (a) Gm1 m2 21. 兾3 39. 4s3 1 3 3 15. 650,000 ft-lb 17. 3857 J 19. 2450 J 21. ⬇1.06 10 6 J 5 23. ⬇1.04 10 ft-lb 25. 2.0 m x 25. 13兾45 37. 8 45. r 13. (a) 625 ft-lb 1 19. 兾3 3 1. (a) 7200 ft-lb (b) 7200 ft-lb 15 3. 4.5 ft-lb 5. 180 J 7. 4 ft-lb x 1 1 32 4 3 EXERCISES 6.4 y=1-¥ 0 35. N (b) ⬇8.50 10 9 J PAGE 453 1. 3. 5. 共2兾兲共e 1兲 9. (a) 1 (b) 2, 4 (c) 8 3 7. 2兾共5兲 45 28 33. (a) 2 x02 8s1 x 2兾4 dx ⬇ 78.95684 (b) 2 x01 8s4 4y 2 dy ⬇ 78.95684 11 35. 1.288, 0.884; 23.780 37. 8 2 x , 39. Solid obtained by rotating the region 0 0 y ssin x about the x-axis 41. Solid obtained by rotating the region above the x-axis bounded by x 苷 y 2 and x 苷 y 4 about the y-axis 43. 1110 cm 3 45. (a) 196 (b) 838 1 1 2 47. 3 r 2h 49. h2 (r 3 h) 51. 3 b 2h 1 8 3 53. 10 cm 55. 24 57. 3 59. 15 61. (a) 8R x0r sr 2 y 2 dy (b) 2 2r 2R 63. (b) r 2h 65. EXERCISES 6.3 N 5 12 r 3 11. (a) 4兾 (b) ⬇1.24, 2.81 (c) 67. 8 x0r sR 2 y 2 sr 2 y 2 dy PAGE 444 1. Circumference 苷 2 x, height 苷 x 共x 1兲2; 兾15 9 8 15. 17. 共50 28兾兲 F ⬇ 59 F 19. 6 kg兾m 21. About 4056 million (or 4 billion) people 23. 5兾共4兲 ⬇ 0.4 L CHAPTER 6 REVIEW 3. 6兾7 5. 共1 1兾e兲 7. 8 15. 7兾15 17. 8兾3 13. 16兾3 21. (a) 2 x x e 2 0 2 x dx 11. 768兾7 19. 5兾14 x0 2 共4 y兲 ssin y dy PAGE 457 Exercises 1. 8 3 3. 7 12 4 5. 3 2 3兾2 11. 共2ah h 兲 4 3 (b) 4.06300 23. (a) 4 x兾2 共 x兲 cos4 x dx 兾2 25. (a) 9. 4 N 4兾 13. 7. 64 兾15 15. (a) 2兾15 (b) 兾6 (c) 8兾15 17. (a) 0.38 (b) 0.87 19. Solid obtained by rotating the region 0 (b) 46.50942 (b) 36.57476 9. 1656兾5 x兾3兾3 2 (兾2 x)(cos 2x 14 ) dx x 兾2 about the y-axis 21. Solid obtained by rotating the region 0 0 y 2 sin x about the x-axis 125 23. 36 25. 3 s3 m 3 27. 3.2 J 29. (a) 8000兾3 ⬇ 8378 ft-lb (b) 2.1 ft y cos x , x , 0 27. 3.68 29. Solid obtained by rotating the region 0 y x 4, 0 x 3 about the y-axis 31. Solid obtained by rotating the region bounded by (i) x 苷 1 y 2, x 苷 0, and y 苷 0, or (ii) x 苷 y 2, x 苷 1, and y 苷 0 about the line y 苷 3 31. f 共x兲 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA086-095.qk_97909_Ans_Ans_pA086-095 10/7/10 2:36 PM Page 95 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I PROBLEMS PLUS N PAGE 459 EXERCISES 7.2 1. (a) f 共t兲 苷 3t (b) f 共x兲 苷 s2x兾 (c) 0.6736 m 5. (b) 0.2261 2 3. 32 27 (c) f 共 y兲 苷 sk A兾共 C兲 y 1兾4. Advantage: the markings on the container are equally spaced. 13. b 苷 2a 15. B 苷 16A N 1 3 ⱍ ⱍ 37. 41. ⱍ ⱍ ⱍ ⱍ ⱍ ⱍ ⱍ F _π e 2x 2 23. C 4共2x 1兲 2 2 81 1 3 27. 4 ln 3 5 29. 4 4 e2 1 1兾e 1 33. sin x 共ln sin x 1兲 C 6 ( 6 3 s3 ) 32 64 62 2 5 共ln 2兲 25 ln 2 125 1 39. 2 兾4 2 sx sin sx 2 cos sx C 1 1 2 1 3 2 2 共x 1兲 ln共1 x兲 4 x 2 x 4 C π f _π 53. 1 6 sin 3x 1 18 sin 9x C 1 ƒ F _2 43. 12 xe2x 14 e2x C ⱍ π 1 25. 31. 35. ⱍ ⱍ 17. 13 e 2共2 sin 3 3 cos 3 兲 C 19. z 3e z 3z 2e z 6ze z 6e z C 21. 1 5 3 ⱍ PAGE 468 1 1 x 3 ln x 19 x 3 C 3. 5 x sin 5x 25 cos 5x C 1 3t 1 3t 5. 3 te 9 e C 7. 共x 2 2x兲 sin x 共2x 2兲 cos x 2 sin x C 1 3 9. x ln s 11. t arctan 4t 8 ln共1 16t 2 兲 C x 13 x C 1 1 13. 2 t tan 2t 4 ln sec 2t C 15. x 共ln x兲2 2x ln x 2x C 1. 1 3 ⱍ CHAPTER 7 EXERCISES 7.1 PAGE 476 N 1 sin x sin5 x C 3. 120 1 2 1 5. sin 3 共 x兲 sin 5 共 x兲 sin 7 共 x兲 C 3 5 7 7. 兾4 9. 3兾8 11. 兾16 1 1 1 13. 4 t 2 4 t sin 2t 8 cos 2t C 2 15. 45 ssin 共45 18 sin 2 5 sin 4 兲 C 1 17. 2 cos 2x ln cos x C 19. ln sin x 2 sin x C 1 21. 3 sec3 x C 23. tan x x C 1 2 1 117 25. 9 tan9 x 7 tan7 x 5 tan5 x C 27. 8 1 3 29. 3 sec x sec x C 1 31. 4 sec 4x tan 2x ln sec x C 1 33. x sec x ln sec x tan x C 35. s3 3 22 8 37. 105 s2 105 39. ln csc x cot x C 1 1 1 1 41. 6 cos 3x 26 cos 13x C 43. 8 sin 4 12 sin 6 C 1 1 45. 2 s2 47. 2 sin 2x C 1 49. x tan x ln sec x 2 x 2 C 1 2 1 2 2 51. 4 x 4 sin共x 兲 cos共x 兲 C 1. (d) (i) 1兾共105兲 ⬇ 0.003 in兾s (ii) 370兾3 s ⬇ 6.5 min 32 9. y 苷 9 x 2 11. (a) V 苷 x0h 关 f 共 y兲兴 2 dy A95 2 1 f _1 3 F 1 55. 0 57. 1 59. 0 65. s 苷 共1 cos 3 t兲兾共3兲 61. 2兾4 63. (2s2 5 2 ) _1 EXERCISES 7.3 45. 3 x 2 共1 x 2 兲3兾2 1 2 15 共1 x 2 兲5兾2 C 1. 4 _2 2 f _4 47. (b) cos x sin x x 49. 55. 57. 61. 67. sin 2x C (b) 23 , x 关共ln x兲 3共ln x兲2 6 ln x 6兴 C 16 29 59. 1.75119, 1.17210; 3.99926 3 ln 2 9 4 8兾 63. 2 e 65. 1 共2兾 兲 ln 2 69. 2 2 et共t 2 2t 2兲 m 3 3 8 PAGE 483 s4 x 2 C 4x 3. sx 2 4 2 sec1 冉冊 x 2 C 1 1 s3 7. 24 8 4 s2 a 2 1 1 9. ln (sx 2 16 x) C 11. 4 sin1共2x兲 2 x s1 4x 2 C 1 1 2 2 13. 6 sec 共x兾3兲 sx 9兾共2x 兲 C 1 15. 16 a 4 17. sx 2 7 C 9 19. ln (s1 x 2 1)兾x s1 x 2 C 21. 500 9 1 23. 2 sin1共共x 2兲兾3兲 2 共 x 2兲s5 4x x 2 C 1 1 25. sx 2 x 1 2 ln (sx 2 x 1 x 2 ) C 1 1 2 2 27. 2 共x 1兲 sx 2x 2 ln x 1 sx 2x C 1 1 29. 4 sin1 共x 2 兲 4 x 2 s1 x 4 C 1 3 3 33. 6 (s48 sec1 7) 37. 8 2 4 41. 2 2Rr 2 43. r sR 2 r 2 r 2兾2 R 2 arcsin共r兾R兲 5. F 1 4 8 15 3 N 3 16 ⱍ ⱍ ⱍ ⱍ Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA096-105.qk_97909_Ans_Ans_pA096-105 10/7/10 2:38 PM Page 96 A96 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I EXERCISES 7.4 PAGE 492 N (b) A A B B C 1. (a) (b) 2 4x 3 2x 5 x x 5 2x B C Dx E A 3. (a) 2 3 2 x x x x 4 B D C A (b) x3 共x 3兲 2 x3 共x 3兲 2 B A 5. (a) x 4 4x 2 16 x2 x2 Cx D Ex F Ax B 2 2 (b) 2 x x1 x 2 共x 2兲2 1 1 1 7. 4 x 4 3 x 3 2 x 2 x ln x 1 C ⱍ ⱍ ⱍ ⱍ ⱍ ⱍ 27 5 ⱍ ⱍ ⱍ ⱍ ⱍ 3 29. 1 2 ln共x 2 2x 5兲 32 tan1 31. 1 3 ln x 1 16 ln共x 2 x 1兲 ⱍ ⱍ 33. 1 4 ln 83 35. 冉 冊 1 16 ⱍ ⱍ ln x 321 冉 冊 37. s2 tan1 7 8 x2 s2 x1 2 ⱍ ⱍ 53. ( x 1 2 ⱍ ⱍ 1 57. 1 2 ln 冟 冟 x2 C x 61. 1 5 ln 冟 21. 共x 1兲 arctan sx sx C ⱍ 23 3 ⱍ ⱍ ⱍ 冉 冊 35. 1 8 x1 2 x1 s3 2x x 2 C 2 sin 4x 161 sin 8x C ⱍ ⱍ ⱍ ⱍ 37. ⱍ ⱍ 1 4 39. ln sec 1 ln sec C 1 3 ⱍ ⱍ 43. 2 3 tan1共 x 3兾2 兲 C 47. ln x 1 3共x 1兲1 2 共x 1兲2 3 共x 1兲3 C 冟 3 1 冟 冟 冟 s4x 1 1 s4x 2 1 1 51. ln C C 2x s4x 1 1 2 2 1 2 53. x cosh共mx兲 2 x sinh共mx兲 3 cosh共mx兲 C m m m 55. 2 ln sx 2 ln (1 sx ) C 3 3 57. 7 共x c兲7兾3 4 c共x c兲4兾3 C 59. sin共sin x兲 3 sin 3 共sin x兲 C 61. csc cot C or tan共兾2兲 C 1 冉 2x 1 s7 冊 C 冟 2 tan共x兾2兲 1 C tan共x兾2兲 2 11 24,110 1 668 1 9438 1 4879 5x 2 323 2x 1 80,155 3x 7 1 22,098x 48,935 260,015 x2 x 5 69. (a) 25. 3x 33. 2 sin1 49. ln 63. 4 ln 3 2 65. 1 3 ln 2 1 67. t 苷 ln P 9 ln共0.9P 900兲 C, where C ⬇ 10.23 2 C 45. 共x 3 1兲ex C ⱍ ) ln共x 2 x 2兲 2x s7 tan1 55. 2 ln 3 ⬇ 0.55 19. e 1 3 ⱍ 2 2 ln(sx 1) C sx 3 3 43. 10 共x 2 1兲5兾3 4 共x 2 1兲2兾3 C 3 6 6 x 6 ln s x1 C 45. 2 sx 3 sx 6 s ⱍ 15. x兾s1 x 2 C 1 ex 41. tan 2 2 ln sec C 39. 2sx 1 ln(sx 1 1) ln sx 1 1 C ⱍ 2 1 2 4 4097 45 31. sin1x s1 x 2 C C 3x 8 C 4共x 2 4x 6兲 共e x 2兲2 C 47. ln ex 1 49. ln tan t 1 ln tan t 2 C 51. x ln共e x 1兲 C ⱍ ln x 4 53 ln x 2 C 27. x ln 共1 e x 兲 C 29. x ln( x sx 2 1 ) sx 2 1 C 23. 1 2x 1 tan1 C s3 s3 1 ln共x 2 4兲 C 8共x 2 4兲 41. 2 ln sx ⱍ 冉 冊 17. ⱍ ln共x 2 1兲 (1兾s2 ) tan1(x兾s2 ) C 3 1 25. 2 ln x 1 ln共x 2 1兲 2 tan1 x C 1 2 ⱍ PAGE 499 N 13. 5 cos5 t 7 cos7 t 9 cos9 t C 1 27. ⱍ 1 t tan1 C 7. e 兾4 e兾4 2s2 s2 243 242 1 9. 5 ln 3 25 11. 2 ln共x 2 4x 5兲 tan1共x 2兲 C 5. 23. ln x 1 2 ln共x 2 9兲 3 tan1共x兾3兲 C ⱍ ⱍ 2 ⱍ 1 ⱍ 1. sin x sin x C 3. sin x ln csc x cot x C 1 3 5 19. 10 ln x 3 9 ln x 2 C x2 1 2 2 1 21. 2 x 2 ln共x 4兲 2 tan 共x兾2兲 C ⱍ ⱍ EXERCISES 7.5 ln 2 95 ln 3 (or 95 ln 83) ⱍ ⱍ 11,049 75,772 2x 1 tan1 C ln共x 2 x 5兲 260,015 260,015 s19 s19 The CAS omits the absolute value signs and the constant of integration. 1 1 1 1 73. n n n1 2 a 共x a兲 a x a x ax n 9. 12 ln 2x 1 2 ln x 1 C 11. 2 ln 2 7 2 13. a ln x b C 15. 6 ln 3 17. 334 3146 4822 ln 5x 2 ln 2x 1 ln 3x 7 4879 323 80,155 63. 2( x 2sx 2) e sx C 65. tan1 共cos 2 x兲 C 67. 3 关共x 1兲3兾2 x 3兾2 兴 C 2 69. s2 2兾s3 ln (2 s3 ) ln (1 s2 ) 71. e x ln共1 e x 兲 C 73. s1 x 2 2 共arcsin x兲 2 C 1 75. 1 8 ⱍ ⱍ ln x 2 161 ln共x 2 4兲 18 tan1共x兾2兲 C s1 e x 1 C s1 e x 1 1 1 1 79. 3 x sin3 x 3 cos x 9 cos3x C 77. 2共x 2兲s1 e x 2 ln 81. 2s1 sin x C 2 83. xe x C Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA096-105.qk_97909_Ans_Ans_pA096-105 10/7/10 2:38 PM Page 97 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I EXERCISES 7.6 1. 5. N 23. (a) 2.8 (b) 7.954926518 (c) 0.2894 (d) 7.954926521 (e) The actual error is much smaller. (f ) 10.9 (g) 7.953789422 (h) 0.0593 (i) The actual error is smaller. ( j) n 50 PAGE 504 3. s13 4 ln(4 s13 ) 2 4 ln 3 5 21 3 1 1 1 4 ln(1 16 2) 8 7. 9. s4x 2 9兾共9x兲 C 1 6 ln 冟 3 冟 sin x 3 C sin x 3 25. 11. e 2 ⱍ ⱍ 13. 2 tan2共1兾z兲 ln cos共1兾z兲 C 1 15. 共e 2x 1兲 arctan共e x 兲 e x C 1 2 17. 1 2 冉 2y 1 2y 1 7 s6 4y 4y 2 sin1 8 8 s7 1 2 3兾2 12 共6 4y 4y 兲 C 冊 冟 1 9 sin 3x 关3 ln共sin x兲 1兴 C 23. 1 4 tan x sec 3x tan x sec x ln sec x tan x C 3 8 ⱍ 3 8 [ ] ⱍ 25. 2 共ln x兲s4 共ln x兲 2 2 ln ln x s4 共ln x兲 2 C 1 27. x 1 2 2 1 2 cos 共x 兲 s1 x 1 2 4 冟 e x s3 1 ln x C 2s3 e s3 19. 21. 37. 1 5 1 3 1 4 1 4 1 4 ⱍ ⱍ n Ln 5 10 20 0.742943 0.867782 0.932967 n EL ER ET EM 5 10 20 0.257057 0.132218 0.067033 0.286599 0.139610 0.068881 0.014771 0.003696 0.000924 0.007379 0.001848 0.000462 27. 43. C 冟 冟 ⱍ N PAGE 516 1. (a) L 2 苷 6, R2 苷 12, M2 ⬇ 9.6 (b) L 2 is an underestimate, R2 and M2 are overestimates. (c) T2 苷 9 I (d) L n Tn I Mn Rn 3. (a) T4 ⬇ 0.895759 (underestimate) (b) M4 ⬇ 0.908907 (overestimate) T4 I M4 5. (a) M10 ⬇ 0.806598, E M ⬇ 0.001879 (b) S10 ⬇ 0.804779, E S ⬇ 0.000060 7. (a) 1.506361 (b) 1.518362 (c) 1.511519 9. (a) 2.660833 (b) 2.664377 (c) 2.663244 11. (a) 2.591334 (b) 2.681046 (c) 2.631976 13. (a) 4.513618 (b) 4.748256 (c) 4.675111 15. (a) 0.495333 (b) 0.543321 (c) 0.526123 17. (a) 8.363853 (b) 8.163298 (c) 8.235114 19. (a) T8 ⬇ 0.902333, M8 ⬇ 0.905620 (b) ET 0.0078, EM 0.0039 (c) n 苷 71 for Tn , n 苷 50 for Mn 21. (a) T10 ⬇ 1.983524, ET ⬇ 0.016476; M10 ⬇ 2.008248, EM ⬇ 0.008248; S10 ⬇ 2.000110, ES ⬇ 0.000110 (b) ET 0.025839, EM 0.012919, E S 0.000170 (c) n 苷 509 for Tn , n 苷 360 for Mn , n 苷 22 for Sn ⱍ ⱍ ⱍ ⱍ ⱍ ⱍ ⱍ ⱍ 0.992621 0.998152 0.999538 Mn Sn 6.695473 6.474023 n ET EM ES 6 12 0.295473 0.074023 0.147428 0.036992 0.003292 0.000206 6.252572 6.363008 6.403292 6.400206 Observations are the same as after Example 1. (a) 19.8 (b) 20.6 (c) 20.53 (a) 14.4 (b) 12 64.4 F 35. 37.73 ft兾s 37. 10,177 megawatt-hours (a) 190 (b) 828 6.0 43. 59.4 29. 31. 33. 39. 41. 45. 1 s1 x 2 C; x both have domain 共1, 0兲 傼 共0, 1兲 EXERCISES 7.7 Mn 3 cos3 x sin x 38 x 38 sin x cos x C tan 4 x 12 tan 2 x ln cos x C 45. (a) ln 1.014771 1.003696 1.000924 6 12 tan x sec 2 x 23 tan x C ⱍ 1.286599 1.139610 1.068881 Tn 39. x共x 2 2兲 sx 2 4 2 ln (sx 2 4 x) C 41. Tn n 33. 8 2 ln x 5 sx 10 2 C Rn Observations are the same as after Example 1. 29. se 2x 1 cos1共ex 兲 C 31. A97 ⱍ ⱍ y 1 0 0.5 EXERCISES 7.8 1 N 1.5 2 x PAGE 527 Abbreviations: C, convergent; D, divergent 1. (a), (d) Infinite discontinuity (b), (c) Infinite interval 3. 1兾共2t 兲; 0.495, 0.49995, 0.4999995; 0.5 1 5. 2 7. D 9. 5 e 10 11. D 13. 0 15. D 1 1 17. ln 2 19. 4 21. D 23. 兾9 25. 2 27. D 32 9 29. 3 31. D 33. 2 35. D 37. 2兾e 8 8 39. 3 ln 2 9 1 41. 1兾e 43. 2 ln 2 1 2 2 2 y y=e_x y= 1 ˛+x x=1 0 1 x 0 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 3 97909_Ans_Ans_pA096-105.qk_97909_Ans_Ans_pA096-105 10/7/10 2:38 PM Page 98 A98 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 45. Infinite area ⱍ 冟 π 2 0 y t t 1 关共sin 2x兲兾x 2 兴 dx 2 5 10 100 1,000 10,000 33. x x sin1 2 s4 x 2 1 4 41. 1 36 47. 1 2 sin 2x 18 cos 4x C 43. D 49. 兾4 4 3 57. 61. 63. 65. 67. 69. 71. 73. sin x s4 sin 2 x 2 ln (sin x s4 sin 2 x ) C No (a) 1.925444 (b) 1.920915 (c) 1.922470 (a) 0.01348, n 368 (b) 0.00674, n 260 8.6 mi (a) 3.8 (b) 1.7867, 0.000646 (c) n 30 (a) D (b) C 3 2 75. 16 2 1 2 PROBLEMS PLUS y=F(t) t (in hours) ⱍ (b) The rate at which the fraction F共t兲 increases as t increases (c) 1; all bulbs burn out eventually N PAGE 534 1. About 1.85 inches from the center 3. 0 7. f 共兲 苷 兾2 11. 共b baa 兲1兾共ba兲e1 13. 18 121 15. 2 sin1 (2兾s5 ) CHAPTER 8 69. 1000 71. (a) F共s兲 苷 1兾s, s 0 (b) F共s兲 苷 1兾共s 1兲, s (c) F共s兲 苷 1兾s 2, s 0 77. C 苷 1; ln 2 79. No 1 EXERCISES 8.1 1. 4s5 7. 13. PAGE 530 19. True-False Quiz N PAGE 543 3. 3.8202 5. 3.6095 (82 s82 1) 9. 5924 11. 323 3 1 15. 4 2 ln 2 17. ln(s2 1) 21. 10.0556 s2 ln (1 s2 ) 2 243 23. 15.374568 27. (a), (b) 1. False 3. False 5. False 7. False 9. (a) True (b) False 11. False 13. False ln 3 12 25. 7.118819 L 1 苷 4, L 2 ⬇ 6.43, L 4 ⬇ 7.50 Exercises 1. 7. 7 2 2 15 ln 2 ⱍ ln 2x 1 s4x 2 4x 3 C 55. 57. p 1, 1兾共1 p兲 65. s2GM兾R 700 37. C 1 1 N 冉冊 3 55. 4 共2x 1兲s4 x 2 4x 3 10 CHAPTER 7 REVIEW 31. 6 2 29. 0 51. 共x 1兲 ln共x 2 2x 2兲 2 arctan共x 1兲 2x C 53. 0 0.1 0 2 5 45. 4 ln 4 8 sin@ x ≈ 49. C 51. D 53. D 59. p 1, 1兾共 p 1兲2 y 67. (a) 27. 1 1 ≈ 1 3 2 39. 8 e 0.447453 0.577101 0.621306 0.668479 0.672957 0.673407 ©= ln共x 2 1兲 3 tan1x s2 tan1(x兾s2 ) C 25. 35. 4s1 sx C It appears that the integral is convergent. (c) 1 ƒ= 冟 sx 2 1 1 C 23. ln x y=sec@ x 47. (a) ⱍ 21. ln x 2 sx 2 4x C 20 ⱍ 3. e 1 ⱍ ⱍ ⱍ 5. ln 2t 1 ln t 1 C 11. s3 3 9. cos共ln t兲 C 1 13. 3e sx 共x 2兾3 2x 1兾3 2兲 C 3 ⱍ ⱍ ⱍ ⱍ 15. 2 ln x 2 ln x 2 C 1 3 ⱍ ⱍ 17. x sec x ln sec x tan x C 19. 1 18 ln共9x 2 6x 5兲 1 9 tan1 [ (3x 1)] C 1 2 (c) x04 s1 关4共3 x兲兾共3共4 x兲2兾3 兲兴 2 dx (d) 7.7988 29. s5 ln ( 2 (1 s5 )) s2 ln (1 s2 ) 1 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA096-105.qk_97909_Ans_Ans_pA096-105 10/7/10 2:38 PM Page 99 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 31. 6 EXERCISES 8.5 N A99 PAGE 573 1. (a) The probability that a randomly chosen tire will have a 33. s共x兲 苷 2 27 [共1 9x兲3兾2 10 s10 ] 37. 209.1 m 39. 29.36 in. EXERCISES 8.2 1. (a) (i) (ii) 兾3 0 x (ii) 5. x 1 27 x N PAGE 550 2 tan x s1 sec 4 x dx 2 x s1 sec 4 x dx 3. (a) (i) 1 0 兾3 0 1 1 x 35. 2 s2 (s1 x 1) 41. 12.4 x 2 2 e s1 (b) (i) 10.5017 (ii) 7.9353 2 4x 2e 2x dx 2 x s1 4x 2e 2x dx 2 (145 s145 1) 7. (b) (i) 11.0753 98 3 (ii) 3.9603 11. 21 2 23. [ [ln(s10 3) 3 s10 ] 27. (a) 3 a 2 1 (b) 冋 29. (a) 2 b 2 冋 (b) 2 a 2 31. 56 45 a 2b sin1(sa 2 b 2兾a) sa 2 b 2 ab 2 sin1(sb 2 a 2兾b) sb 2 a 2 册 xab 2 关c f 共x兲兴 s1 关 f 共x兲兴 2 dx EXERCISES 8.3 N CHAPTER 8 REVIEW ] 册 冉 冉( 冊 3. (a) 冊 7. 13. (2, 3 ) 15. 2 2 21. (a) 1 e3兾8 ⬇ 0.31 (c) 8 ln 2 ⬇ 5.55 min 11. 2 3 25. ( 23, 23) 3. (a) 2r共r d 兲 (b) ⬇3.36 (d) ⬇7.84 2 15. 1.19 104 cm 3兾s 7 10 mi 10 6 mi 2 7. Height s2 b, volume ( 27 s6 2)b 3 11. 2兾, 1兾 13. 共0, 1兲 28 9. 0.14 m CHAPTER 9 45. 3 r 2h 1 5. $407.25 13. PAGE 577 r e x兾H ⴢ 2 sr 2 x 2 dx (b) 共P0 0 tH兲共r 2 兲 0 tHe L兾H xr 共1 k兲共b 2k a 2k 兲 共2 k兲共b 1k a 1k 兲 17. 6.60 L兾min 19. 5.77 L兾min (16s2 8) ⬇ $9.75 million N (b) e5兾4 ⬇ 0.29 5. (a) P共z兲 苷 P0 t x0z 共x兲 d x PAGE 566 3. $140,000; $60,000 9. 3727; $37,753 ( 85 , 1) 1 2 EXERCISES 9.1 3. (a) , 1 1. $21,104 7. $12,000 11. 1. s3 2 3 1 2 EXERCISES 8.4 9. ⬇ 458 lb 124 5 5. 3.8202 PROBLEMS PLUS 10 5 lb 23. 10; 14; 共1.4, 1兲 41 10 (b) 17. $7166.67 0 for all x and x f 共x兲 dx 苷 1 (b) ⬇ 0.3455 (c) 5, yes 33. 4 2r 2 1 e1 9 9 29. ( 20 , 20 ) , e1 4 s2 4 1 8 1 31. 33. ( 5, 2 ) , 4 s2 1) 4 (s2 1) 8 1 12 1 35. 60; 160; ( 3, 1) 37. ( 5, 35 ) 41. (0, 12 ) N 21 16 19. (a) f 共x兲 1. (a) 187.5 lb兾ft 2 (b) 1875 lb (c) 562.5 lb 3. 6000 lb 5. 6.7 7. 9.8 10 4 N 10 3 N 2 4 2 9. 1.2 11. 3 ah 10 lb 13. 5.27 15. (a) 314 N 10 5 N (b) 353 N 17. (a) 5.63 10 3 lb (b) 5.06 10 4 lb 27. 15 2 2 PAGE 560 (c) 4.88 10 4 lb (d) 3.03 19. 4148 lb 21. 330; 22 PAGE 575 N Exercises 1. s3 a 2 3 (e) 2 a0 21. 4 4 ln(s17 4) 4 ln(s2 1) s17 4 s2 1 6 4x10–10 0 (d) 1 41e8 ⬇ 0.986 9. 2s1 2 共2兾兲 ln ( s1 2 ) 1 13. 27 (145 s145 10 s10 ) 15. a 2 19. 24.144251 17. 1,230,507 1 lifetime between 30,000 and 40,000 miles (b) The probability that a randomly chosen tire will have a lifetime of at least 25,000 miles 3. (a) f 共x兲 0 for all x and x f 共x兲 dx 苷 1 (b) 17 81 1 5. (a) 1兾 (b) 2 7. (a) f 共x兲 0 for all x and x f 共x兲 dx 苷 1 (b) 5 4兾2.5 11. (a) e ⬇ 0.20 (b) 1 e2兾2.5 ⬇ 0.55 (c) If you aren’t served within 10 minutes, you get a free hamburger. 13. ⬇44% 15. (a) 0.0668 (b) ⬇5.21% 17. ⬇0.9545 19. (b) 0; a0 (c) 1x10 10 N PAGE 584 5. (d) 7. (a) It must be either 0 or decreasing (c) y 苷 0 (d) y 苷 1兾共x 2兲 9. (a) 0 P 4200 (b) P 4200 (c) P 苷 0, P 苷 4200 13. (a) III (b) I (c) IV (d) II 15. (a) At the beginning; stays positive, but decreases Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA096-105.qk_97909_Ans_Ans_pA096-105 10/7/10 2:39 PM Page 100 A100 (c) APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES 17. P(t) M 2 c 2; 2, 0, 2 c=3 y 2 c=1 P(0) 0 _1 t 0 t 1 c=_1 _2 EXERCISES 9.2 N 1. (a) PAGE 592 c=_3 y 2.0 (iv) 19. (a) (i) 1.4 1.5 1.0 0.5 (b) _2 _1 (iii) 1.4641 (iii) (ii) Underestimates y=´ h=0.1 h=0.2 h=0.4 1.5 1.4 1.3 1.2 (i) 0 (ii) 1.44 y 2 x 1 1.1 1.0 (b) y 苷 0.5, y 苷 1.5 0 3. III 7. 0.1 0.2 0.3 0.4 x 5. IV 9. y (c) (i) 0.0918 (ii) 0.0518 (iii) 0.0277 It appears that the error is also halved (approximately). y (b) (a) 3 21. 1, 3, 6.5, 12.25 23. 1.7616 (ii) 2.3928 (iii) 2.3701 (iv) 2.3681 (c) (i) 0.6321 (ii) 0.0249 (iii) 0.0022 (iv) 0.0002 It appears that the error is also divided by 10 (approximately). 27. (a), (d) (b) 3 (c) Yes; Q 苷 3 Q 6 (e) 2.77 C 25. (a) (i) 3 3 x _3 _3 (c) _3 0 3 x _3 4 11. 13. y 3 y 3 2 0 3x _3 3x _3 EXERCISES 9.3 _3 4 t 2 _3 N PAGE 600 2 1. y 苷 ,y苷0 K x2 ⱍ ⱍ 3 3x 3 ln x K 3. y 苷 s 5. 2 y 2 cos y 苷 2 x 2 4 x 4 C 1 1 15. 1 1 t 2 2 3 9. p 苷 Ke t 兾3t 1 7. e 共 y 1兲 苷 C e y 4 11. y 苷 sx 2 9 13. u 苷 st 2 tan t 25 15. 2 y 2 3 共3 y 2 兲 3兾2 苷 2 x 2 ln x 4 x 2 1 _3 3 17. y 苷 1 1 41 12 4a sin x a s3 2 _2 1 19. y 苷 e x 兾2 21. y 苷 Ke x x 1 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA096-105.qk_97909_Ans_Ans_pA096-105 10/7/10 2:39 PM Page 101 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 23. (a) sin1y 苷 x 2 C 43. (a) C共t兲 苷 共C0 r兾k兲ekt r兾k (b) y 苷 sin共x 兲, s兾2 x s兾2 2 (b) r兾k; the concentration approaches r兾k regardless of the value of C0 45. (a) 15et兾100 kg (b) 15e0.2 ⬇ 12.3 kg 47. About 4.9% 49. t兾k (b) B 苷 KV 0.0794 51. (a) L 1 苷 KL 2k (c) No 1 y=sin (≈) 53. (a) dA兾dt 苷 k sA 共M A兲 _œ„„„ _œ π/2 A101 œπ/2 „„„ 0 25. cos y 苷 cos x 1 where C 苷 5 (b) A共t兲 苷 M sM sA0 and A0 苷 A共0兲 sM sA0 EXERCISES 9.4 N 冉 CesM kt 1 Ce sM kt 1 冊 2 , PAGE 613 1. (a) 100; 0.05 (b) Where P is close to 0 or 100; on the line P 苷 50; 0 P0 100; P0 100 (c) P 2.5 27. (a) 2.5 P¸=140 P¸=120 1 (b) y 苷 Kx P¸=80 P¸=60 0 y 3 150 100 50 P¸=40 P¸=20 0 0 _3 3 x _3 29. y 苷 Cx 2 4 _4 4 _4 31. x 2 y 2 苷 C ≈-¥=C 4 20 Solutions approach 100; some increase and some decrease, some have an inflection point but others don’t; solutions with P0 苷 20 and P0 苷 40 have inflection points at P 苷 50 (d) P 苷 0, P 苷 100; other solutions move away from P 苷 0 and toward P 苷 100 10 7 kg (b) ⬇1.55 years 3. (a) 3.23 5. 9000 1 7. (a) dP兾dt 苷 265 P共1 P兾100兲, P in billions (b) 5.49 billion (c) In billions: 7.81, 27.72 (d) In billions: 5.48, 7.61, 22.41 y0 9. (a) dy兾dt 苷 ky共1 y兲 (b) y 苷 y0 共1 y0 兲ekt (c) 3:36 PM 13. PE 共t兲 苷 1578.3共1.0933兲t 94,000; 32,658.5 PL共t兲 苷 94,000 1 12.75e0.1706t xy=k _4 60 t 40 130,000 4 PL P (in thousands) PE _4 33. y 苷 1 e 2x 兾2 35. y 苷 2 4t 37. Q共t兲 苷 3 3e ;3 kt 39. P共t兲 苷 M Me 4 41. (a) x 苷 a (kt 2兾sa ) 2 冉 冑 2 tan1 (b) t 苷 ksa b ( 12 x 2 2) 2 ;M 冑 冊 b tan1 ab 0 90,000 1960 bx ab 冉 45 1980 t (year) 2000 冊 m m kt P0 e (b) m kP0 k k (c) m 苷 kP0 , m kP0 (d) Declining 15. (a) P共t兲 苷 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA096-105.qk_97909_Ans_Ans_pA096-105 10/7/10 2:39 PM Page 102 A102 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 17. (a) Fish are caught at a rate of 15 per week. (c) P 苷 250, P 苷 750 0 P0 250: P l 0; P0 苷 250: P l 250; P0 250: P l 750 (b) See part (d). (d) P 1200 800 27. (a) I共t兲 苷 4 4e5t (b) 4 4e1兾2 ⬇ 1.57 A 29. Q共t兲 苷 3共1 e4t 兲, I共t兲 苷 12e4t 31. P共t兲 苷 M Cekt P(t) M 400 P(0) 0 0 40 33. y 苷 5 共100 2t兲 40,000共100 2t兲3兾2; 0.2275 kg兾L 2 250 750ke t兾25 1 ke t兾25 1 where k 苷 11 , 19 (e) P共t兲 苷 P 1200 (c) 共mt兾c兲关t 共m兾c兲ect兾m 兴 m 2t兾c 2 M 37. (b) P共t兲 苷 1 MCe kt 35. (b) mt兾c 120 t 0 19. (b) 0 P0 200: P l 0; P0 苷 200: P l 200; P0 200: P l 1000 P 1400 1200 1000 800 600 400 200 0 (c) P共t兲 苷 20 40 60 100 t 80 m共M P0兲 M共P0 m兲e 共Mm兲共k兾M 兲t M P0 共P0 m兲e 共Mm兲共k兾M 兲t 21. (a) P共t兲 苷 P0 e 共k兾r兲关sin共rt 兲 sin 兴 EXERCISES 9.5 1. Yes N 7. y 苷 x 1 Ce 11. y 苷 1. (a) x 苷 predators, y 苷 prey; growth is restricted only by predators, which feed only on prey. (b) x 苷 prey, y 苷 predators; growth is restricted by carrying capacity and by predators, which feed only on prey. 3. (a) Competition (b) (i) x 苷 0, y 苷 0: zero populations (ii) x 苷 0, y 苷 400: In the absence of an x-population, the y-population stabilizes at 400. (iii) x 苷 125, y 苷 0: In the absence of a y-population, the x-population stabilizes at 125. (iv) x 苷 50, y 苷 300: Both populations are stable. 5. (a) The rabbit population starts at about 300, increases to 2400, then decreases back to 300. The fox population starts at 100, decreases to about 20, increases to about 315, decreases to 100, and the cycle starts again. (b) R F R 2000 5. y 苷 1 Ce x PAGE 627 N 2500 x 9. y 苷 sx C兾x x sin共x 2兲 dx C 200 1000 100 500 t 2 2t 2C 13. u 苷 2共t 1兲 0 17. u 苷 t 2 t 3 7. C=3 C=5 C=7 Species 2 t=2 150 C=3 C=5 C=7 5 t t¡ t™ t£ 200 共x 1兲e x C x2 300 F 1500 2 3 sin x 1 1 3 15. y 苷 ln x 2 x x x 19. y 苷 x cos x x 21. y 苷 (b) Does not exist EXERCISES 9.6 PAGE 620 3. No t 120 t 80 t=3 t=1 100 t=4 C=1 _3 50 t=0, 5 3 0 C=_5 C=_3 C=_1 冉 25. y 苷 Cx 4 2 5x 冊 1兾2 _5 C=_5 C=_3 C=_1 50 100 150 200 250 Species 1 11. (a) Population stabilizes at 5000. (b) (i) W 苷 0, R 苷 0: Zero populations (ii) W 苷 0, R 苷 5000: In the absence of wolves, the rabbit population is always 5000. (iii) W 苷 64, R 苷 1000: Both populations are stable. Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA096-105.qk_97909_Ans_Ans_pA096-105 10/7/10 2:39 PM Page 103 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I (d) (c) The populations stabilize at 1000 rabbits and 64 wolves. (d) W R (birds) y 250 35,000 80 W 1500 x (insects) 45,000 birds 200 150 25,000 60 insects 100 15,000 1000 40 R 500 0 50 5,000 20 0 t t 25. (a) y 苷 共1兾k兲 cosh kx a 1兾k or y 苷 共1兾k兲 cosh kx 共1兾k兲 cosh kb h CHAPTER 9 REVIEW N PAGE 629 True-False Quiz 1. True 3. False PROBLEMS PLUS 5. True 1. f 共x兲 苷 10e 7. True (b) 共2兾k兲 sinh kb PAGE 633 5. y 苷 x 1兾n 冉冊 7. 20 C x x L 12 L ln 4L L 9. (b) f 共x兲 苷 1. (a) N x 2 Exercises A103 2 (c) No 11. (a) 9.8 h (b) 31,900 ft 2; 2000 ft 2兾h (c) 5.1 h 13. x 2 共 y 6兲2 苷 25 15. y 苷 K兾x, K 苷 0 y 6 (iv) 4 (iii) 2 CHAPTER 10 (ii) (i) 0 t 1 EXERCISES 10.1 1. y y共0.3兲 ⬇ 0.8 y 3 2 2 0 PAGE 641 3. t=_2 (2, 6) (b) 0 c 4; y 苷 0, y 苷 2, y 苷 4 3. (a) N _2 _1 0 1 2 t=2 (6, 2) t= t=0 (0, 0) t= 2 5. (a) 3x y y苷 (12 x 2 C) esin x 0 9. r共t兲 苷 5e tt 2 11. y 苷 2 x 共ln x兲2 2x 1 13. x 苷 C 2 y 2 1 2000 15. (a) P共t兲 苷 ; ⬇560 1 19e0.1t (b) t 苷 10 ln 572 ⬇ 33.5 17. (a) L共t兲 苷 L 关L L共0兲兴ekt (b) L共t兲 苷 53 43e0.2t 19. 15 days 21. k ln h h 苷 共R兾V 兲t C 23. (a) Stabilizes at 200,000 (b) (i) x 苷 0, y 苷 0: Zero populations (ii) x 苷 200,000, y 苷 0: In the absence of birds, the insect population is always 200,000. (iii) x 苷 25,000, y 苷 175: Both populations are stable. (c) The populations stabilize at 25,000 insects and 175 birds. π 3 1 x (b) y 苷 34 x 14 (7, 5) t=_1 (3, 2) t=0 x (_1, _1) t=1 7. y 苷 sln共x 2 2x 3兾2 C兲 t= π 2 π 6 (0, 0) 0 x (b) 0.75676 (c) y 苷 x and y 苷 x; there is a loc max or loc min 5. t=0 (1, 1) 1 1 _3 y (_5, _4) t=2 7. (a) (b) x 苷 共 y 2兲2 1, 4 y 0 y (_3, 0) t=2 (0, _1) t=1 x (1, _2) t=0 (_3, _4) t=_2 (0, _3) t=_1 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA096-105.qk_97909_Ans_Ans_pA096-105 10/7/10 2:39 PM Page 104 A104 9. (a) APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES (b) y 苷 1 x 2, x y π 29. 0 (0, 1) t=0 (1, 0) t=1 x 0 _4 4 (2, _3) t=4 _π 11. (a) x 2 y 2 苷 1, y 0 (b) _1 13. (a) y 苷 1兾x, y (b) 1 31. (b) x 苷 2 5t, y 苷 7 8t, 0 t 1 33. (a) x 苷 2 cos t, y 苷 1 2 sin t, 0 t 2 y 1 1 x 0 (b) x 苷 2 cos t, y 苷 1 2 sin t, 0 t 6 (c) x 苷 2 cos t, y 苷 1 2 sin t, 兾2 t 3兾2 37. The curve y 苷 x 2兾3 is generated in (a). In (b), only the portion with x 0 is generated, and in (c) we get only the portion with x 0. 41. x 苷 a cos , y 苷 b sin ; 共x 2兾a 2 兲 共 y 2兾b 2 兲 苷 1, ellipse 43. y y 2a x O (1, 1) 0 x 45. (a) Two points of intersection 4 15. (a) y 苷 ln x 1 1 2 (b) y 6 1 0 6 x 1 4 17. (a) y 2 x 2 苷 1, y (b) (b) One collision point at 共3, 0兲 when t 苷 3兾2 (c) There are still two intersection points, but no collision point. 0, there is a loop whose size 47. For c 苷 0, there is a cusp; for c increases as c increases. 1 y 3 1 1 _1 1 2 0 x 0 1 0 1.5 0 1.5 19. Moves counterclockwise along the circle 共x 3兲2 共 y 1兲2 苷 4 from 共3, 3兲 to 共3, 1兲 21. Moves 3 times clockwise around the ellipse 共x 2兾25兲 共 y 2兾4兲 苷 1, starting and ending at 共0, 2兲 23. It is contained in the rectangle described by 1 x 4 and 2 y 3. 25. 27. y y 1 _3 _1 49. The curves roughly follow the line y 苷 x, and they start having loops when a is between 1.4 and 1.6 (more precisely, when a s2 ). The loops increase in size as a increases. 51. As n increases, the number of oscillations increases; a and b determine the width and height. 1 t= 2 (0, 1) t=1 (_1, 0) t=0 x (0, _1) t=_1 t=0 EXERCISES 10.2 1 x N 2t 1 t cos t sin t 7. y 苷 2x 1 1. PAGE 651 3. y 苷 2 x 7 3 5. y 苷 x 2 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA096-105.qk_97909_Ans_Ans_pA096-105 10/7/10 2:39 PM Page 105 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 9. y 苷 6 x 1 57. 20 59. 61. 65. _10 15. 17. 19. 2 1215 24 5 (247 s13 64) (949 s26 1) 63. 5 a 2 6 71. 1 4 10 _2 11. x0兾2 2 t cos t st 2 1 dt ⬇ 4.7394 x01 2 共t 2 1兲e tse 2t 共t 1兲 2共t 2 2t 2兲 dt ⬇ 103.5999 EXERCISES 10.3 2t 1 1 , 3, t 0 13. e 2t共1 t兲, e 3t共2t 3兲, t 2t 4t 32 tan t, 34 sec 3 t, 兾2 t 3兾2 Horizontal at 共0, 3兲, vertical at 共2, 2兲 Horizontal at ( 12 , 1) and ( 12 , 1), no vertical 21. 共0.6, 2兲; (5 ⴢ 6 6兾5, e 6 23. 7.5 1兾5 ) 25. y 苷 x, y 苷 x 3 2 PAGE 662 N 1. (a) π ”2, 3 ’ (b) π 3 O O 共2, 7兾3兲, 共2, 4兾3兲 (c) y _ 3π ”1, _ 3π ’ 4 4 共1, 5兾4兲, 共1, 兾4兲 π 2 8.5 3 0 x O 1 π ”_1, 2 ’ 27. (a) d sin 兾共r d cos 兲 29. ( 27, 9 ), 共2, 4兲 31. ab 33. 3 e 35. 2r 2 d 2 37. x02 s2 2e 2t dt ⬇ 3.1416 共1, 3 兾2兲, 共1, 5兾2兲 16 29 39. x04 s5 4 cos t dt ⬇ 26.7298 43. s2 ln (1 s2 ) 45. s2 共e 1兲 1 2 3. (a) (b) π (1, π) 41. 4s2 2 O O _ 2π 1 2 3 ”2, _ 2π ’ 3 8 (1, s3 ) 共1, 0兲 (c) 3π 4 25 47. 16.7102 0 2.5 O 1.4 3π ”_2, 4 ’ (s2, s2 ) _2.1 2.1 5. (a) (i) (2s2, 7兾4) (b) (i) 共2, 2兾3兲 (ii) (2s2, 3兾4) (ii) 共2, 5兾3兲 7. _1.4 r=1 49. 612.3053 55. (a) 51. 6 s2, s2 t 僆 关0, 4兴 15 15 15 O 9. ¨= 15 (b) 294 3π 4 π ¨= 4 O Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. A105 97909_Ans_Ans_pA106-115.qk_97909_Ans_Ans_pA106-115 10/14/10 6:24 PM Page 106 A106 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 11. ¨= 49 7π 3 51. x=1 r=3 r=2 (2, 0) (6, 0) O O ¨= 13. 17. 19. 21. 25. 29. 5π 3 53. (a) For c ⬍ ⫺1, the inner loop begins at sin⫺1 共⫺1兾c兲 and ends at ⫺ sin⫺1 共⫺1/c兲; for c ⬎ 1, it begins at ⫹ sin⫺1 共1兾c兲 and ends at 2 ⫺ sin⫺1 共1兾c兲. 2s3 15. Circle, center O, radius s5 Circle, center 共1, 0兲, radius 1 Hyperbola, center O, foci on x-axis r 2 csc 23. r 1兾共sin ⫺ 3 cos 兲 27. (a) 兾6 r 2c cos (b) x 3 55. s3 57. ⫺ 59. 1 61. Horizontal at (3兾s2, 兾4), (⫺3兾s2, 3兾4); vertical at 共3, 0兲, 共0, 兾2兲 3 3 63. Horizontal at ( 2 , 兾3), 共0, 兲 [the pole], and ( 2 , 5兾3); 31. vertical at (2, 0), ( 2 , 2兾3), ( 2 , 4兾3) 1 O (4, 0) 1 65. Center 共b兾2, a兾2兲, radius sa 2 ⫹ b 2兾2 O 67. 69. 2.6 3.5 (2, 3π/2) _3.4 33. 35. 1.8 _3 3 π ¨= 3 5 2 π ”4, 6 ’ (2π, 2π) O _2.5 _2.6 1 6 71. 3 37. ¨= 39. π 8 ¨= 4 5π 6 ¨= (2, 0) π 6 73. By counterclockwise rotation through angle 兾6, 兾3, or ␣ about the origin O 75. For c 0, the curve is a circle. As c increases, the left side gets flatter, then has a dimple for 0.5 ⬍ c ⬍ 1, a cusp for c 1, and a loop for c ⬎ 1. 41. 43. (3, π/6) (3, π/4) EXERCISES 10.4 ⫺ 兾4 1. e 9. O O ⫺e N PAGE 668 ⫺ 兾2 3. 5. 2 7. 11. 11 9 2 (2, π/2) 41 4 (3, π/2) (1, π) (5, 0) O 45. ¨= 2π 3 π ¨= 3 47. r=2 sin ¨ 13. 2 9 1 (3, π) (3, 3π/2) O 2 3 (3, 0) O 1 _4 4 _3 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA106-115.qk_97909_Ans_Ans_pA106-115 10/14/10 6:24 PM Page 107 APPENDIX I 15. 2 3 ANSWERS TO ODD-NUMBERED EXERCISES 11. 共0, ⫾2兲, (0, ⫾s2 ) 1.4 13. 共⫾3, 0兲, (⫾2s2 , 0) y 2 _2.1 2.1 y 1 2 œ„ 2œ„2 _2œ„2 0 _3 _1.4 17. 3 4 19. 1 16 33. 1 ⫺ 2 s2 1 37. 35. 1 4 29. 5 24 1 ⫺ 14 s3 1 31. 2 ⫺ 1 1 ( ⫹ 3 s3 ) _1 15. 共1, ⫾3兲, (1, ⫾s5 ) ( 32, 兾6), ( 32, 5兾6), and the pole y and 共⫺1, 兲 where 7兾12, 11兾12, 19兾12, 23兾12 1 1 41. ( 2 s3, 兾3), ( 2 s3, 2兾3), and the pole 43. Intersection at ⬇ 0.89, 2.25; area ⬇ 3.46 8 45. 2 47. 3 关共 2 ⫹ 1兲3兾2 ⫺ 1兴 16 3 x _2 39. 共1, 兲 where 兾12, 5兾12, 13兾12, 17兾12 49. 2 œ„ 3 x 2 _œ„ 23. 3 ⫹ 2 s3 3 27. 25. 4 s3 ⫺ 43 0 2 _œ„ 21. ⫺ 2 s3 A107 1 17. x2 y2 ⫹ 1, foci (0, ⫾s5 ) 4 9 (1, 3) ⫺1 0 3 x (1,_3) 19. 共0, ⫾5兲; (0, ⫾s34 ); y ⫾ 3 x 5 y y=53 x {0, œ„„ 34} _0.75 1.25 (3, 5) (0, 5) x _1 (0, _5) 51. 2.4221 53. 8.0091 55. (b) 2 (2 ⫺ s2 ) y=_ 53x {0, _ œ„„ 34} EXERCISES 10.5 1. 共0, 0兲, (0, 3 2 N PAGE 676 ), y ⫺ 32 3. 共0, 0兲, (⫺2,, 0), x 1 y 2 y 6 1 2 21. 共⫾10, 0兲, (⫾10 s2 , 0), y ⫾x y y=x (10, 10) x=21 {_10œ„ 2, 0} (_10, 0) (10, 0) {10œ„ 2, 0} x ”0, 32’ (_1/2, 0) 6 x x _2 y=_x y=-32 23. 共4, ⫺2兲, 共2, ⫺2兲; y (3⫾s5, ⫺2); 5. 共⫺2, 3兲, 共⫺2, 5兲, y 1 7. 共⫺2, ⫺1兲, 共⫺5, ⫺1兲, x 1 y y ⫹ 2 ⫾2共x ⫺ 3兲 0 y (2, _2) (_2, 5) (3-œ„5, _2) 0 (_5, _1) y=1 x (4, _2) (3+œ„5, _2) x (_2, _1) x 25. Parabola, 共0, ⫺1兲, (0, ⫺4 ) 27. Ellipse, (⫾s2, 1), 共⫾1, 1兲 29. Hyperbola, 共0, 1兲, 共0, ⫺3兲; (0, ⫺1 ⫾ s5 ) 3 x=1 9. x ⫺y 2, focus (⫺ 4 , 0), directrix x 1 1 4 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA106-115.qk_97909_Ans_Ans_pA106-115 10/14/10 6:24 PM Page 108 A108 31. y 2 4x 41. 45. 49. 51. 55. 59. 61. 63. 35. y ⫺ 3 2共x ⫺ 2兲2 33. y 2 ⫺12共x ⫹ 1兲 x x y 共 y ⫺ 4兲 ⫹ 1 ⫹ 1 39. 25 21 12 16 2 2 2 x 共x ⫹ 1兲 共 y ⫺ 4兲 y2 ⫹ 1 ⫺ 1 43. 12 16 9 16 2 2 2 2 x 共 y ⫺ 1兲 共x ⫹ 3兲 y ⫺ 1 ⫺ 1 47. 25 39 9 36 2 2 x y ⫹ 1 3,763,600 3,753,196 121x 2 121y 2 (a) ⫺ 1 (b) ⬇248 mi 1,500,625 3,339,375 (a) Ellipse (b) Hyperbola (c) No curve 15.9 b 2c a ⫹ ab ln where c 2 a 2 ⫹ b 2 a b⫹c 共0, 4兾 兲 2 37. ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 2 2 2 15. (a) 2 (d) 3 1 ”- 4 , 0’ ” 4 , π’ O 3 x=_ 8 17. (a) 2, y ⫺ 2 1 冉 冊 EXERCISES 10.6 N (c) x ⫺ 38 (b) Hyperbola 1 _2 2 1 y=-2 _3 PAGE 684 6 4 3. r 2 ⫹ cos 2 ⫹ 3 sin 8 4 5. r 7. r 1 ⫺ sin 2 ⫹ cos 4 (b) Ellipse (c) y ⫺1 9. (a) 5 (d) y 1. r 1 (b) r 1 ⫺ 2 sin共 ⫺ 3兾4兲 2 _2 2 (4, π/2) _2 ” 45 , π’ 19. The ellipse is nearly circular when e is close to 0 and becomes more elongated as e l 1⫺. At e 1, the curve becomes a parabola. ” 45 , 0’ O x 4 3π ”9, 2 ’ 11. (a) 1 y=_1 (c) y 23 (b) Parabola (d) y e=0.4 e=1.0 e=0.6 e=0.8 2.26 ⫻ 10 8 1 ⫹ 0.093 cos 27. 35.64 AU 29. 7.0 ⫻ 10 7 km 25. r 31. 3.6 ⫻ 10 8 km y=2/3 ”31 , π 2’ ” 23, π’ CHAPTER 10 REVIEW ” 23, 0’ O N True-False Quiz 1. False 3. False x PAGE 685 5. True 7. False 9. True Exercises 1. x y 2 ⫺ 8y ⫹ 12 13. (a) 1 3 (b) Ellipse (d) (c) x 9 2 3. y 1兾x y y (0, 6), t=_4 9 x= 2 3 π ” 2, 2 ’ 9 9 ” 4 , π’ ” 8 , 0’ (5, 1), t=1 (1, 1), ¨=0 O x x 3 3π ” 2, 2 ’ 5. x t, y st ; x t 4, y t 2; x tan 2 t, y tan t, 0 艋 t ⬍ 兾2 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA106-115.qk_97909_Ans_Ans_pA106-115 10/14/10 6:24 PM Page 109 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 7. (a) 43. All curves have the vertical asymptote x 1. For c ⬍ ⫺1, the curve bulges to the right. At c ⫺1, the curve is the line x 1. For ⫺1 ⬍ c ⬍ 0, it bulges to the left. At c 0 there is a cusp at (0, 0). For c ⬎ 0, there is a loop. (b) (3s2, 3兾4), (⫺3s2, 7兾4) ”4, 2π ’ 3 A109 2π 3 O 47. (⫺ 24 , 3), 共⫺1, 3兲 45. 共⫾1, 0兲, 共⫾3, 0兲 25 y y 2 œ„2 (1, 0) (⫺2, 2s3 ) ⫺3 9. 0 11. (_1, 3) x 3 ⫺2œ„2 ¨= π ”1, 2 ’ 0 x π 6 49. (1, 0) (2, π) O y2 x2 ⫹ 1 25 9 y2 x2 ⫺ 1 72兾5 8兾5 51. 共8y ⫺ 399兲2 4 x2 55. r ⫹ 1 25 160,801 3 ⫹ cos 3 3 57. (a) At (0, 0) and ( 2 , 2 ) 3 3 (b) Horizontal tangents at (0, 0) and (s 2, s 4 ); 3 3 vertical tangents at (0, 0) and (s4, s2 ) (g) 32 (d) y 53. 3π ”1, 2 ’ 13. 15. ”_3, 3π ’ 2 1 (2, π) (2, 0) 3 y= 2 O _1 ”1, π ’ 2 17. r 2 cos ⫹ sin 19. x y ⫽ ⫺x ⫺ 1 O 0.75 r= sin ¨ ¨ -0.3 1.2 PROBLEMS PLUS N 1. ln共兾2兲 [ PAGE 688 ] 3. ⫺4 s3, 4 s3 ⫻ 关⫺1, 2兴 3 3 CHAPTER 11 -0.75 21. 2 25. EXERCISES 11.1 23. ⫺1 1 ⫹ sin t 1 ⫹ cos t ⫹ sin t , 1 ⫹ cos t 共1 ⫹ cos t兲3 27. 1. (a) A sequence is an ordered list of numbers. It can also be defined as a function whose domain is the set of positive integers. (b) The terms an approach 8 as n becomes large. (c) The terms an become large as n becomes large. y ( 32 a, ⫾ 12 s3 a), 共⫺3a, 0兲; horizontal tangent at 1 3 共a, 0兲, (⫺2 a, ⫾ 2 s3 a) PAGE 700 Abbreviations: C, convergent; D, divergent ( 118 , 34 ) 29. Vertical tangent at N 4 3 8 5. 5, ⫺ 25, 125, ⫺ 625, 3125 5 1 3. 1, 5, 5, 17 , 13 (⫺3a, 0) (a, 0) x 0 9. 1, 2, 7, 32, 157 33. 共2, ⫾兾3兲 37. 2(5 s5 ⫺ 1) 39. 35. 2 共 ⫺ 1兲 1 冉 2 s 2 ⫹ 1 ⫺ s4 2 ⫹ 1 2 ⫹ s4 2 ⫹ 1 ⫹ ln 2 ⫹ s 2 ⫹ 1 41. 471,295兾1024 冊 1 1 2 2 2 2 3 5 7 9 11. 2, , , , 1 1 1 1 1 1 7. 2, 6, 24, 120 , 720 13. a n 1兾共2n ⫺ 1兲 n2 n⫹1 19. 0.4286, 0.4615, 0.4737, 0.4800, 0.4839, 0.4865, 0.4884, 1 0.4898, 0.4909, 0.4918; yes; 2 21. 0.5000, 1.2500, 0.8750, 1.0625, 0.9688, 1.0156, 0.9922, 1.0039, 0.9980, 1.0010; yes; 1 23. 1 25. 5 27. 1 29. 1 31. D 33. 0 35. D 37. 0 39. 0 41. 0 43. 0 45. 1 47. e 2 49. ln 2 51. 兾2 53. D 55. D 1 57. 1 59. 2 61. D 63. 0 65. (a) 1060, 1123.60, 1191.02, 1262.48, 1338.23 (b) D 2 n⫺1 15. a n ⫺3(⫺ 3 ) 31. 18 1 17. a n 共⫺1兲 n⫹1 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA106-115.qk_97909_Ans_Ans_pA106-115 10/14/10 6:24 PM Page 110 A110 67. 69. 71. 73. 77. 79. 85. APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES (a) Pn 1.08Pn⫺1 ⫺ 300 (b) 5734 ⫺1 ⬍ r ⬍ 1 Convergent by the Monotonic Sequence Theorem; 5 艋 L ⬍ 8 Decreasing; yes 75. Not monotonic; no Decreasing; yes 1 1 2 81. 2 (3 ⫹ s5 ) 83. (b) 2 (1 ⫹ s5 ) (a) 0 (b) 9, 11 EXERCISES 11.2 N 1. (a) A sequence is an ordered list of numbers whereas a series is the sum of a list of numbers. (b) A series is convergent if the sequence of partial sums is a convergent sequence. A series is divergent if it is not convergent. 3. 2 5. 1, 1.125, 1.1620, 1.1777, 1.1857, 1.1903, 1.1932, 1.1952; C 7. 0.5, 1.3284, 2.4265, 3.7598, 5.3049, 7.0443, 8.9644, 11.0540; D (b) 5 (b) 157.895 mg 73. 1 2 (s3 ⫺ 1) 1 79. The series is divergent. n共n ⫹ 1兲 85. 兵sn 其 is bounded and increasing. 77. 1 2 5 23 1 2 7 1 8 共n ⫹ 1兲! ⫺ 1 共n ⫹ 1兲! 119 89. (a) 2 , 6 , 24 , 120 ; EXERCISES 11.3 1. C N (c) 1 PAGE 720 y y= a™ 1 x 1.3 a£ 10 0 ssn d 2 1 a¢ 3 a∞ ... 4 x 3. D 5. C 7. D 9. C 11. C 13. D 15. C 17. C 19. C 21. D 23. C 25. C 27. f is neither positive nor decreasing. 29. p ⬎ 1 31. p ⬍ ⫺1 33. 共1, ⬁兲 9 35. (a) 10 4 (b) 901 4 ⫺ 17 16 37. (a) 1.54977, error 艋 0.1 (b) 1.64522, error 艋 0.005 10 (c) 1.64522 compared to 1.64493 39. 0.00145 45. b ⬍ 1兾e (d) n ⬎ 1000 ssn d EXERCISES 11.4 san d 11 0 1 N PAGE 726 1. (a) Nothing (b) C 3. C 5. D 7. C 9. D 11. C 13. C 15. D 17. D 19. D 21. C 23. C 25. D 27. C 29. C 31. D 33. 1.249, error ⬍ 0.1 35. 0.0739, error ⬍ 6.4 ⫻ 10 ⫺8 45. Yes ssn d EXERCISES 11.5 san d 11 0 25 1 (a) C (b) D 17. D 19. 3 21. 60 23. 7 5 D 27. D 29. D 31. 2 33. D 35. D 3 11 D 39. D 41. e兾共e ⫺ 1兲 43. 2 45. 6 47. e ⫺ 1 (b) 1 (c) 2 (d) All rational numbers with a terminating decimal representation, except 0. 8 838 51. 9 53. 333 55. 5063兾3300 1 1 ⫺5x 3 57. ⫺ ⬍ x ⬍ ; 59. ⫺1 ⬍ x ⬍ 5; 5 5 1 ⫹ 5x 5⫺x x 1 61. x ⬎ 2 or x ⬍ ⫺2; 63. x ⬍ 0; x⫺2 1 ⫺ ex 2 65. 1 67. a1 0, an for n ⬎ 1, sum 1 n共n ⫹ 1兲 15. 25. 37. 49. D共1 ⫺ c n 兲 1⫺c 71. (a) Sn san d 0 1.98637, 2.88080, 3.80927, 4.75796, 5.71948, 6.68962, 7.66581, 8.64639; divergent 13. 0.29289, 0.42265, 0.50000, 0.55279, 0.59175, 0.62204, 0.64645, 0.66667, 0.68377, 0.69849; convergent, sum 1 共1 ⫺ 0.05 n兲 1 _3 11. 0.44721, 1.15432, 3000 19 87. (a) 0, 9 , 9 , 3 , 3 , 9 , 9 , 1 PAGE 711 9. ⫺2.40000, ⫺1.92000, ⫺2.01600, ⫺1.99680, ⫺2.00064, ⫺1.99987, ⫺2.00003, ⫺1.99999, ⫺2.00000, ⫺2.00000; convergent, sum ⫺2 69. (a) 157.875 mg; N PAGE 731 1. (a) A series whose terms are alternately positive and negative (b) 0 ⬍ bn⫹1 艋 bn and lim n l ⬁ bn 0, where bn an (c) Rn 艋 bn⫹1 3. C 5. C 7. D 9. C 11. C 13. D 15. C 17. C 19. D 21. ⫺0.5507 23. 5 25. 4 27. ⫺0.4597 29. 0.0676 31. An underestimate 33. p is not a negative integer 35. 兵bn 其 is not decreasing ⱍ ⱍ EXERCISES 11.6 N ⱍ ⱍ PAGE 737 Abbreviations: AC, absolutely convergent; CC, conditionally convergent 1. (a) D 3. AC 15. AC 27. AC (b) C 5. CC 17. CC 29. D (c) May converge or diverge 7. AC 9. D 11. AC 13. AC 19. AC 21. AC 23. D 25. AC 31. D 33. AC Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA106-115.qk_97909_Ans_Ans_pA106-115 10/14/10 6:24 PM Page 111 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I ⬁ 35. (a) and (d) 661 39. (a) 960 ⬇ 0.68854, error ⬍ 0.00521 19. (b) n 艌 11, 0.693109 ⬁ 共⫺1兲 n ⬁ 共⫺1兲 n⫺1 45. (b) 兺 ; 兺 n n2 n ln n n1 21. 兺 共2n ⫹ 1兲x , R 1 n n0 ⬁ 兺 共⫺1兲 n n0 1 x 2n⫹1, R 4 16n⫹1 s£ 0.25 EXERCISES 11.7 1. C 13. C 25. C 33. C N EXERCISES 11.8 s¡ PAGE 740 3. D 15. C 27. C 35. D 4 s™ s¢ f s∞ s¡ 1. A series of the form 冘⬁n0 cn共x ⫺ a兲n, where x is a variable 13. 4, 共⫺4, 4兴 25. , [ , 1] 31. k k 1 23. ] 13 兺 n0 2x 2n⫹1 ,R1 2n ⫹ 1 s£ 1 29. (a) Yes ⫺2 2 (b) No 33. No ⫺3 (b), (c) s¸ s™ s¢ 2 8 41. 2 EXERCISES 11.10 J¡ _8 37. 共⫺1, 1兲, f 共x兲 共1 ⫹ 2x兲兾共1 ⫺ x 2 兲 EXERCISES 11.9 ⬁ 1. 10 1. PAGE 751 兺 共⫺1兲 x , 共⫺1, 1兲 n n 3. ⬁ 5. 2 n0 ⬁ 兺 共⫺1兲 1 n 9 n⫹1 冋 n0 ⬁ 兺 共⫺1兲 n0 n⫹1 x ⫺ 2 n⫹1 册 n0 x , 共⫺1, 1兲 n ⬁ n n n0 (b) 兺 共⫺1兲 共n ⫹ 2兲共n ⫹ 1兲x , R 1 n n n0 兺 共⫺1兲 n共n ⫺ 1兲x , R 1 n n n2 ⬁ xn ,R5 n5 n 兺 n1 ⬁ 兺 共⫺1兲 4 共n ⫹ 1兲x n n0 n b 8 f 共5兲兾8! 兺 x , 共⫺1, 1兲 n , R 14 兺 共n ⫹ 1兲x , R 1 n n0 n 7. 兺 共⫺1兲 2n⫹1 x 2n⫹1, R ⬁ 共2n ⫹ 1兲! n n0 ⬁ ⬁ 共ln 2兲 n n x 2n⫹1 x ,R⬁ ,R⬁ 11. 兺 n! n0 n0 共2n ⫹ 1兲! 2 3 13. ⫺1 ⫺ 2共x ⫺ 1兲 ⫹ 3共x ⫺ 1兲 ⫹ 4共x ⫺ 1兲 ⫹ 共x ⫺ 1兲4, R ⬁ ⬁ 1 15. ln 2 ⫹ 兺 共⫺1兲 n⫹1 共x ⫺ 2兲 n, R 2 n 2n n1 9. 兺 ⬁ 17. 兺 n0 2 ne 6 共x ⫺ 3兲 n, R ⬁ n! ⬁ 19. 兺 共⫺1兲 n⫹1 n0 25. 1 ⫺ n⫹1 ⬁ 3. 兺 共n ⫹ 1兲x , R 1 ⬁ ⬁ PAGE 765 n0 ⬁ 15. ln 5 ⫺ 17. 5. ⬁ 1 2 1 (c) 2 3 n⫹1 x n, 共⫺3, 3兲 N 共8兲 ⬁ 1 n1 兺 共⫺1兲 共n ⫹ 1兲x , R 1 13. (a) 兺 9. 1 ⫹ 2 , 共⫺3, 3兲 2n⫹1 1 兺 s¡ s£ s∞ _2 N ⬁ t 8n⫹2 ,R1 n0 8n ⫹ 2 ⬁ x n⫹3 ,R1 27. C ⫹ 兺 共⫺1兲 n n共n ⫹ 3兲 n1 31. 0.000983 33. 0.19740 29. 0.199989 35. (b) 0.920 39. 关⫺1, 1兴, 关⫺1, 1兲, 共⫺1, 1兲 25. C ⫹ 11. s¡ f 35. (a) 共⫺⬁, ⬁兲 7. s™ 3 11 23. 0, { 2 } 21. b, 共a ⫺ b, a ⫹ b兲 27. ⬁, 共⫺⬁, ⬁兲 3 5 [ 1 1 17. 3 , ⫺ 3 , ⫺ 3 ) 15. 1, 关1, 3兴 19. ⬁, 共⫺⬁, ⬁兲 1 5 1 _0.25 s£ ⬁ [ 11. 3, ⫺ 3, 3 s¢ s™ _4 PAGE 745 and a and the cn’s are constants 3. 1, 共⫺1, 1兲 5. 1, 关⫺1, 1兲 7. ⬁, 共⫺⬁, ⬁兲 9. 2, 共⫺2, 2兲 s∞ f 5. C 7. D 9. C 11. C 17. C 19. C 21. D 23. D 29. C 31. D 37. C N A111 ⬁ 3 ⴢ 7 ⴢ ⭈ ⭈ ⭈ ⴢ 共4n ⫺ 5兲 n 1 x⫺ 兺 x ,R1 4 4 n ⴢ n! n2 ⬁ 27. 兺 共⫺1兲 n n0 1 共x ⫺ 兲2n, R ⬁ 共2n兲! 共n ⫹ 1兲共n ⫹ 2兲 n x ,R2 2 n⫹4 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA106-115.qk_97909_Ans_Ans_pA106-115 10/14/10 6:24 PM Page 112 A112 ⬁ 29. 兺 共⫺1兲 n n0 ⬁ 31. 兺 n0 2n⫹1 x 2n⫹1, R ⬁ 共2n ⫹ 1兲! EXERCISES 11.11 兺 共⫺1兲 n n0 N PAGE 774 1. (a) T0 共x兲 1 T1共x兲, T2共x兲 1 ⫺ 2 x 2 T3共x兲, 1 1 1 T4共x兲 1 ⫺ 2 x 2 ⫹ 24 x 4 T5共x兲, 2n ⫹ 1 n x ,R⬁ n! ⬁ 33. ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 1 1 1 T6共x兲 1 ⫺ 2 x 2 ⫹ 24 x 4 ⫺ 720 x 6 T¢=T∞ 1 x 4n⫹1 , R ⬁ 2 共2n兲! 2 T¸=T¡ 2n 35. ⬁ 1 1 ⴢ 3 ⴢ 5 ⴢ ⭈ ⭈ ⭈ ⴢ 共2n ⫺ 1兲 2n⫹1 x ⫹ 兺 共⫺1兲n x ,R2 2 n! 2 3n⫹1 n1 37. 兺 共⫺1兲 ⬁ f _2π 2π 2 2n⫺1 2n x ,R⬁ 共2n兲! n⫹1 n1 _2 Tß ⬁ 1 x 4n, R ⬁ 39. 兺 共⫺1兲n 共2n兲! n0 (b) T¸=T¡=T™=T£ _1.5 1.5 Tˆ=T˜=T¡¸=T¡¡ T2 T3 T4 T5 0.7071 1 0.6916 0.7074 0.7071 0 1 ⫺0.2337 0.0200 ⫺0.0009 ⫺1 1 ⫺3.9348 0.1239 ⫺1.2114 T6 (c) As n increases, Tn共x兲 is a good approximation to f 共x兲 on a larger and larger interval. f 3. T¢=T∞=Tß=T¶ _1.5 T0 T1 x 4 2 1.5 f T™=T£ 1 2 ⫺ 14 共x ⫺ 2兲 ⫹ 18 共x ⫺ 2兲 2 ⫺ 161 共x ⫺ 2兲3 2 ⬁ 41. 共⫺1兲 x n, R ⬁ 共n ⫺ 1兲! n⫺1 兺 n1 f T£ 6 T£ T∞ T¡ 冉 冊 冉 冊 4 T¡ T™ T™ 5. ⫺ x ⫺ T¢ Tß 2 ⫹ f T£ 1 x⫺ 6 2 f T£ 45. (a) 1 ⫹ 0 ⬁ 兺 n1 (b) x ⫹ ⬁ 兺 n1 T£ f _1.1 7. 共x ⫺ 1兲 ⫺ 2 共x ⫺ 1兲 2 ⫹ 3 共x ⫺ 1兲 3 1 ⬁ x 6n⫹2 47. C ⫹ 兺 共⫺1兲 n ,R⬁ 共6n ⫹ 2兲共2n兲! n0 1 2 T£ ⬁ 1 49. C ⫹ 兺 共⫺1兲 n x 2n, R ⬁ 2n 共2n兲! n1 1 53. 0.40102 55. 2 51. 0.0059 3 8 65. ln 5 25 24 x4 67. 1兾s2 61. 1 ⫹ 6 x 2 ⫹ 1 69. e 3 ⫺ 1 π π 2 1 ⴢ 3 ⴢ 5 ⴢ ⭈ ⭈ ⭈ ⴢ 共2n ⫺ 1兲 2n x 2 n n! 1 ⴢ 3 ⴢ 5 ⴢ ⭈ ⭈ ⭈ ⴢ 共2n ⫺ 1兲 2n⫹1 x 共2n ⫹ 1兲2 n n! 59. 1 ⫺ 2 x 2 ⫹ 3 1.1 _6 T¢ T∞ Tß 43. 0.99619 4 0 f _3 f _1 57. 7 360 x4 3 1 120 63. e ⫺x 4 _4 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA106-115.qk_97909_Ans_Ans_pA106-115 10/14/10 6:24 PM Page 113 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I A113 ⬁ 1 1 ⴢ 5 ⴢ 9 ⴢ ⭈ ⭈ ⭈ ⴢ 共4n ⫺ 3兲 n x , R 16 ⫹ 兺 2 n! 2 6n⫹1 n1 ⬁ xn 55. C ⫹ ln x ⫹ 兺 n1 n ⴢ n! 9. x ⫺ 2x 2 ⫹ 2x 3 53. 3 ⱍ ⱍ _1 1.5 57. (a) 1 ⫹ 2 共x ⫺ 1兲 ⫺ 8 共x ⫺ 1兲2 ⫹ 1 (b) T£ f 1 1 16 共x ⫺ 1兲3 (c) 0.000006 1.5 _4 冉 冊 冉 冊 冉 冊 冉 冊 冉 冊 4 11. T5 共x兲 1 ⫺ 2 x ⫺ 4 ⫹2 x⫺ 8 x⫺ 3 4 2 ⫺ 10 ⫹ x⫺ 3 4 4 T£ 3 64 ⫺ x⫺ 15 4 5 f 2 0 59. ⫺ 1 6 T¢ T∞ 5 T£ T™ PROBLEMS PLUS f 0 T™ f T∞ T£ 1 11. ln 2 _2 13. (a) 2 ⫹ 4 共x ⫺ 4兲 ⫺ 1 1 64 1 9 (b) 1.5625 ⫻ 10⫺5 共x ⫺ 4兲2 (a) 1 ⫹ 共x ⫺ 1兲 ⫺ 共x ⫺ 1兲 ⫹ 共x ⫺ 1兲 3 (b) 0.000097 (a) 1 ⫹ x 2 (b) 0.0014 1 (a) 1 ⫹ x 2 (b) 0.00006 21. (a) x 2 ⫺ 6 x 4 (b) 0.042 0.17365 25. Four 27. ⫺1.037 ⬍ x ⬍ 1.037 ⫺0.86 ⬍ x ⬍ 0.86 31. 21 m, no (c) They differ by about 8 ⫻ 10⫺9 km. 2 3 1 2 15. 17. 19. 23. 29. 37. 4 81 2 x 3 ⫹ 4x 2 ⫹ x 共1 ⫺ x兲4 9. 共⫺1, 1兲, 2 π 4 13. (a) 19. ⫺1 2s3 冉 21. ⫺ N True-False Quiz 1. False 3. True 11. True 13. True 19. True 21. True 5. False 15. False 7. False 9. False 17. True 250 101 共e⫺共n⫺1兲兾5 ⫺ e⫺n兾5 兲 1 27. N PAGE 790 3. C; A 5. A vertical plane that intersects the xy-plane in the line y 2 ⫺ x, z 0 z y=2-x 31. e⫺e 37. 0.18976224, error ⬍ 6.4 ⫻ 10 41. 4, 关⫺6, 2兲 1 2 兺 共⫺1兲 n n0 ⬁ 47. 43. 0.5, [2.5, 3.5) ⬁ 兺 共⫺1兲 x 冋 冉 冊 1 x⫺ 共2n兲! 6 ,R1 n n⫹2 2n 51. 兺 共⫺1兲 n n0 冉 冊 册 s3 x⫺ 共2n ⫹ 1兲! 6 49. ln 4 ⫺ n0 ⬁ ⫹ ⬁ 兺 n1 8n⫹4 x ,R⬁ 共2n ⫹ 1兲! x ⱍ ⱍ ⱍ ⱍ y 2 ⱍ ⱍ 7. (a) PQ 6 , QR 2 s10 , RP 6 ; isosceles triangle 9. (a) No (b) Yes 11. 共x ⫹ 3兲 2 ⫹ 共 y ⫺ 2兲 2 ⫹ 共z ⫺ 5兲 2 16; 35. 0.9721 ⫺7 45. y=2-x, z=0 2 29. 兾4 1 11 where k is a positive integer 0 3. D 5. 0 7. e 12 9. 2 11. C 13. C 17. C 19. C 21. C 23. CC 25. AC 250 101 2 Exercises 1. 2 15. D (b) CHAPTER 12 1. 共4, 0, ⫺3兲 PAGE 778 冊 ⫺ k 2 EXERCISES 12.1 CHAPTER 11 REVIEW PAGE 781 1. 15!兾5! 10,897,286,400 3. (b) 0 if x 0, 共1兾x兲 ⫺ cot x if x k, k an integer 2 5. (a) sn 3 ⴢ 4 n, ln 1兾3 n, pn 4 n兾3 n⫺1 (c) 5 s3 T¢ π 2 N 2n⫹1 xn ,R4 n 4n 共 y ⫺ 2兲 2 ⫹ 共z ⫺ 5兲 2 7, x 0 (a circle) 13. 共x ⫺ 3兲2 ⫹ 共 y ⫺ 8兲2 ⫹ 共z ⫺ 1兲2 30 15. 共1, 2, ⫺4兲, 6 17. 共2, 0, ⫺6兲, 9兾s2 5 1 1 19. (b) 2 , 2 s94 , 2 s85 21. (a) 共x ⫺ 2兲2 ⫹ 共 y ⫹ 3兲2 ⫹ 共z ⫺ 6兲2 36 (b) 共x ⫺ 2兲2 ⫹ 共 y ⫹ 3兲2 ⫹ 共z ⫺ 6兲2 4 (c) 共x ⫺ 2兲2 ⫹ 共 y ⫹ 3兲2 ⫹ 共z ⫺ 6兲2 9 23. A plane parallel to the yz-plane and 5 units in front of it Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA106-115.qk_97909_Ans_Ans_pA106-115 10/14/10 6:24 PM Page 114 A114 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 25. A half-space consisting of all points to the left of the plane y 8 27. All points on or between the horizontal planes z 0 and z 6 29. All points on a circle with radius 2 with center on the z-axis that is contained in the plane z ⫺1 31. All points on or inside a sphere with radius s3 and center O 33. All points on or inside a circular cylinder of radius 3 with axis the y-axis 35. 0 ⬍ x ⬍ 5 37. r 2 ⬍ x 2 ⫹ y 2 ⫹ z 2 ⬍ R 2 39. (a) (2, 1, 4) (b) L¡ z C 0 k3, 8, 1l x 3 7 8 1 4 i⫹ j 25. 9 i ⫺ 9 j ⫹ 9 k 27. 60⬚ s58 s58 具 2, 2s3 典 31. ⬇ 45.96 ft兾s, ⬇38.57 ft兾s 100 s7 ⬇ 264.6 N, ⬇139.1⬚ s493 ⬇ 22.2 mi兾h, N8⬚W T1 ⫺196 i ⫹ 3.92 j, T2 196 i ⫹ 3.92 j (a) At an angle of 43.4⬚ from the bank, toward upstream 20.2 min ⫾共i ⫹ 4 j兲兾s17 43. 0 y (a), (b) (d) s 97 , t 117 23. ⫺ 35. 37. 39. (b) 41. 45. sa a PAGE 798 0 1. (a) Scalar (b) Vector (c) Vector (d) Scalar l l l l l l l l 3. AB DC, DA CB, DE EB, EA CE 5. (a) (b) u u+v v w (d) (e) _v u-v (f) u v 15. cos⫺1 _w u w 19. cos⫺1 u-w-v 7. c 2 a ⫹ 2 b, d 2 b ⫺ 2 a 1 1 1 9. a 具4, 1 典 ⬇ 63⬚ 冉 冊 17. cos⫺1 5 s1015 ⬇ 81⬚ [ 27. 共i ⫺ j ⫺ k兲兾s3 or 共⫺i ⫹ j ⫹ k兲兾s3 25. Yes y y ] 35. 1兾s14 , ⫺2兾s14 , ⫺3兾s14 ; 74⬚, 122⬚, 143⬚ A(_1, 3) B(2, 2) A(_1, 1) 0 x 9 7 41. , x a 39. 4, 具 ⫺ 13, 13 典 20 48 37. 1兾s3, 1兾s3, 1兾s3; 55⬚, 55⬚, 55⬚ a 0 1 s5 7. 1 29. 45⬚ 31. 0⬚ at 共0, 0兲, 8.1⬚ at 共1, 1兲 2 1 2 33. 3, 3, 3 ; 48⬚, 71⬚, 48⬚ 11. a 具3, ⫺1 典 B(3, 2) 冉 冊 冉 冊 5. 19 7 21. 48⬚, 75⬚, 57⬚ ⬇ 52⬚ s130 23. (a) Neither (b) Orthogonal (c) Orthogonal (d) Parallel _v v+u+w 1 PAGE 806 N 1. (b), (c), (d) are meaningful 3. 14 1 1 9. ⫺15 11. u ⴢ v 2 , u ⴢ w ⫺ 2 u v+w x b 47. A sphere with radius 1, centered at 共x0, y0, z0 兲 EXERCISES 12.3 v c tb w u+w u (c) y k0, 8, 0l 19. 具2, ⫺18典 , 具1, ⫺42典 , 13, 10 21. ⫺i ⫹ j ⫹ 2 k, ⫺4 i ⫹ j ⫹ 9 k, s14 , s82 y 41. 14x ⫺ 6y ⫺ 10z 9, a plane perpendicular to AB 43. 2 s3 ⫺ 3 N k3, 0, 1l L™ A B EXERCISES 12.2 z 29. 33. P x 17. 具3, 8, 1典 具 27 49 , ,⫺ 54 49 18 49 典 43. 1兾s21, 2 21 i⫺ 1 21 j⫹ 4 21 k 47. 具0, 0, ⫺2 s10 典 or any vector of the form 具s, t, 3s ⫺ 2 s10 典, s, t 僆 ⺢ 13. a 具 2, 0, ⫺2 典 49. 144 J 51. 2400 cos共40⬚兲 ⬇ 1839 ft-lb 13 53. 5 55. cos⫺1(1兾s3 ) ⬇ 55⬚ 15. 具5, 2 典 y z A (0, 3, 1) y a x EXERCISES 12.4 k6, _2l 0 N PAGE 814 1. 16 i ⫹ 48 k 3. 15 i ⫺ 3 j ⫹ 3 k 5. 2 i ⫺ j ⫹ 2 k 7. 共1 ⫺ t兲 i ⫹ 共t 3 ⫺ t 2 兲 k 9. 0 11. i ⫹ j ⫹ k 13. (a) Scalar (b) Meaningless (c) Vector 1 k_1, 4l B (2, 3, _1) k5, 2l 0 x (d) Meaningless (e) Meaningless 3 (f) Scalar Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA106-115.qk_97909_Ans_Ans_pA106-115 10/14/10 6:24 PM Page 115 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 17. 具⫺7, 10, 8 典, 具7, ⫺10, ⫺8典 15. 96s3; into the page 19. 冓 27. 16 31. 33. 41. 45. 冔冓 1 1 5 ⫺ ,⫺ , , 3s3 3s3 3s3 1 1 5 , ,⫺ 3s3 3s3 3s3 29. (a) 具0, 18, ⫺9 典 69. s61兾14 79. 13兾s69 冔 9 2 71. EXERCISES 12.6 (b) s5 (a) 具13, ⫺14, 5 典 (b) s390 9 35. 16 39. 10.8 sin 80⬚ ⬇ 10.6 N ⴢ m ⬇417 N 43. 60⬚ (b) s97兾3 53. (a) No (b) No (c) Yes 1 2 N 73. 5兾 (2s14 ) 18 7 77. 1兾s6 PAGE 832 1. (a) Parabola (b) Parabolic cylinder with rulings parallel to the z-axis (c) Parabolic cylinder with rulings parallel to the x-axis 3. Circular cylinder 5. Parabolic cylinder z z EXERCISES 12.5 N A115 PAGE 824 1. (a) True (b) False (c) True (d) False (e) False (f ) True (g) False (h) True (i) True ( j) False (k) True 3. r 共2 i ⫹ 2.4 j ⫹ 3.5 k兲 ⫹ t共3 i ⫹ 2 j ⫺ k兲; x 2 ⫹ 3t, y 2.4 ⫹ 2t, z 3.5 ⫺ t 5. r 共i ⫹ 6 k兲 ⫹ t共i ⫹ 3 j ⫹ k兲; x 1 ⫹ t, y 3t, z 6 ⫹ t 7. x 2 ⫹ 2t, y 1 ⫹ 2 t, z ⫺3 ⫺ 4t; y x y x 1 7. Hyperbolic cylinder 共x ⫺ 2兲兾2 2y ⫺ 2 共z ⫹ 3兲兾共⫺4兲 y⫺1 x⫹8 ,z4 11 ⫺3 11. x 1 ⫹ t, y ⫺1 ⫹ 2t, z 1 ⫹ t ; x ⫺ 1 共 y ⫹ 1兲兾2 z ⫺ 1 13. Yes 15. (a) 共x ⫺ 1兲兾共⫺1兲 共 y ⫹ 5兲兾2 共z ⫺ 6兲兾共⫺3兲 (b) 共⫺1, ⫺1, 0兲, (⫺ 32 , 0, ⫺ 32), 共0, ⫺3, 3兲 17. r共t兲 共2 i ⫺ j ⫹ 4 k兲 ⫹ t共2 i ⫹ 7 j ⫺ 3 k兲, 0 艋 t 艋 1 19. Skew 21. 共4, ⫺1, ⫺5兲 23. x ⫺ 2y ⫹ 5z 0 25. x ⫹ 4y ⫹ z 4 27. 5x ⫺ y ⫺ z 7 29. 6x ⫹ 6y ⫹ 6z 11 31. x ⫹ y ⫹ z 2 33. ⫺13x ⫹ 17y ⫹ 7z ⫺42 35. 33x ⫹ 10y ⫹ 4z 190 37. x ⫺ 2y ⫹ 4z ⫺1 39. 3x ⫺ 8y ⫺ z ⫺38 y 9. x ⫺8 ⫹ 11t, y 1 ⫺ 3t, z 4; 41. 43. z z 3 2 (0, 0, 10) ”0, 0, ’ y x 9. (a) x k, y 2 ⫺ z 2 1 ⫺ k 2, hyperbola 共k ⫾1兲; y k, x 2 ⫺ z 2 1 ⫺ k 2, hyperbola 共k ⫾1兲; z k, x 2 ⫹ y 2 1 ⫹ k 2, circle (b) The hyperboloid is rotated so that it has axis the y-axis (c) The hyperboloid is shifted one unit in the negative y-direction 11. Elliptic paraboloid with axis the x-axis z (0, _2, 0) 0 (1, 0, 0) 0 (5, 0, 0) (0, 2, 0) y x y x y x 45. 51. 55. 57. 59. 63. 65. 67. 47. 共2, 3, 1兲 49. 1, 0, ⫺1 共2, 3, 5兲 1 Perpendicular 53. Neither, cos⫺1 ( 3 ) ⬇ 70.5⬚ Parallel 5 (a) x 1, y ⫺t, z t (b) cos⫺1 ⬇ 15.8⬚ 3s3 61. x ⫹ 2y ⫹ z 5 x 1, y ⫺ 2 ⫺z 共x兾a兲 ⫹ 共 y兾b兲 ⫹ 共z兾c兲 1 x 3t, y 1 ⫺ t, z 2 ⫺ 2t P2 and P3 are parallel, P1 and P4 are identical 13. Elliptic cone with axis the x-axis z 冉 冊 y x Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA116-125.qk_97909_Ans_Ans_pA116-125 10/14/10 5:00 PM Page 116 A116 APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES 15. Hyperboloid of two sheets 35. 共 y 1兲2 苷 共x 2兲2 共z 1兲2 z (2,-1,1) z Circular cone with vertex 共2, 1, 1兲 and axis parallel to the y-axis y x y x 37. 17. Ellipsoid 39. 4 2 z 0 z 0 z (0, 0, 1) _4 _4 (0, 6, 0) x y y (1, 0, 0) z 41. 19. Hyperbolic paraboloid 0 _2 _2 _4 0 44 x y 0 2 2 0x _2 z=2 z z=œ„„„„„ ≈+¥ 0 y y x x 21. VII 23. II 29. y 2 苷 x 2 25. VI 43. y 苷 x 2 z 2 27. VIII 45. 4x 苷 y 2 z 2, paraboloid x2 y2 z2 苷1 共6378.137兲2 共6378.137兲2 共6356.523兲2 (b) Circle (c) Ellipse 47. (a) z z2 9 51. Elliptic cone with axis the y-axis y 2 z1 0 1 x 31. y 苷 z 2 1 y 0 0 CHAPTER 12 REVIEW x2 2 z 1 1 N PAGE 834 True-False Quiz 1. False 3. False 11. True 13. True 19. False 21. True Hyperbolic paraboloid x 5. True 15. False 7. True 9. True 17. False Exercises y x 共 y 2兲2 33. x 2 共z 3兲2 苷 1 4 (b) 共 y 2兲2 共z 1兲2 苷 68, x 苷 0 (c) Center 共4, 1, 3兲, radius 5 3. u ⴢ v 苷 3 s2; u v 苷 3 s2; out of the page 5. 2, 4 7. (a) 2 (b) 2 (c) 2 (d) 0 1 9. cos1( 3 ) ⬇ 71 11. (a) 具4, 3, 4典 (b) s41兾2 13. 166 N, 114 N 15. x 苷 4 3t, y 苷 1 2t, z 苷 2 3t 17. x 苷 2 2t, y 苷 2 t, z 苷 4 5t 19. 4x 3y z 苷 14 21. (1, 4, 4) 23. Skew 25. x y z 苷 4 27. 22兾s26 ⱍ z (0, 0, 3) (0, 4, 3) Ellipsoid with center 共0, 2, 3兲 0 x 1. (a) 共x 1兲2 共 y 2兲2 共z 1兲2 苷 69 y ⱍ Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA116-125.qk_97909_Ans_Ans_pA116-125 10/14/10 5:00 PM Page 117 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 29. Plane 31. Cone z y 15. 1 z _2π x _1 0 z y 2 y x 2π x 2π x _2π 33. Hyperboloid of two sheets 35. Ellipsoid z _2 z (0, 1, 2) z z 2 y (1, 1, 0) (0, 2, 0) x (0, 0, 2) (0, 2, 0) x y _1 (0, 1,-2) y y 1 x 37. 4x 2 y 2 z 2 苷 16 PROBLEMS PLUS N _2 17. r共t兲 苷 具2 4t, 2t, 2t典 , 0 t 1; PAGE 837 1. (s3 2 ) m 3. (a) 共x 1兲兾共2c兲 苷 共 y c兲兾共c 2 1兲 苷 共z c兲兾共c 2 1兲 3 (b) x 2 y 2 苷 t 2 1, z 苷 t 5. 20 (c) 4兾3 x 苷 2 4t, y 苷 2t, z 苷 2t, 0 t 1 19. r共t兲 苷 具 12 t, 1 43 t, 1 34 t 典 , 0 t 1; x 苷 12 t, y 苷 1 43 t, z 苷 1 34 t, 0 t 1 21. II 23. V 25. IV 27. 29. 共0, 0, 0兲, 共1, 0, 1兲 z CHAPTER 13 0 EXERCISES 13.1 1. 共1, 2兴 7. N y PAGE 845 3. i j k 5. 具1, 兾2, 0典 z 9. y x 31. π 1 (0, 2, 0) y x x 1 z 0 _1 0 x _1 _1 0 y 1 1 33. 11. 13. z z 10 y y=≈ z 0 x 1 x y _10 10 0 x _10 10 0 _10 y Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. A117 97909_Ans_Ans_pA116-125.qk_97909_Ans_Ans_pA116-125 10/14/10 5:00 PM Page 118 A118 35. ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I z 7. (a), (c) 37. 1 2 rª(0) (1, 1) z 0 r(0) 0 2 _1 _1 y 0 1 1 0 y 0 0 0 x 2 2 _1 x 41. r共t兲 苷 t i 2 共t 2 1兲 j 2 共t 2 1兲 k 43. r共t兲 苷 cos t i sin t j cos 2t k, 0 t 2 45. x 苷 2 cos t, y 苷 2 sin t, z 苷 4 cos 2t 47. Yes 1 EXERCISES 13.2 1. (a) (b) r共t兲 苷 2e 2t i e t j y N 1 PAGE 852 y R C r(4.5)-r(4) r(4.5) 1 Q r(4.2) 2 x 9. r共t兲 苷 具t cos t sin t, 2t, cos 2t 2t sin 2t典 11. r共t兲 苷 i (1兾st ) k 2 13. r共t兲 苷 2te t i [3兾共1 3t兲兴 k 15. r共t兲 苷 b 2t c 1 2 2 3 4 17. 具 3 , 3 , 3 典 19. 5 j 5 k 具1, 2t, 3t 2 典 , 具1兾s14, 2兾s14, 3兾s14 典, 具0, 2, 6t典 , 具 6t 2, 6t, 2 典 x 苷 3 t, y 苷 2t, z 苷 2 4t x 苷 1 t, y 苷 t, z 苷 1 t r共t兲 苷 共3 4t兲 i 共4 3t兲 j 共2 6t兲 k x 苷 t , y 苷 1 t , z 苷 2t x 苷 t, y 苷 t, z 苷 t 35. 2 i 4 j 32 k 37. i j k 66° tan t i 18 共t 2 1兲4 j (13 t 3 ln t 19 t 3) k C 2 2 41. t 2 i t 3 j ( 3 t 3兾2 3 ) k 47. 2t cos t 2 sin t 2 cos t sin t 49. 35 21. 23. 25. 27. 29. 31. 33. 39. r(4.2)-r(4) P EXERCISES 13.3 r(4) 0 (b), (d) y R r(4.5) Q T(4) r(4.2) P (c) r共4兲 苷 lim hl0 x r共4 h兲 r共4兲 r共4兲 ; T共4兲 苷 h r共4兲 ⱍ 3. (a), (c) 冊 ⱍ ⱍ 33. (a) P (b) 1.3, 0.7 y=x –@ y=k(x) ⱍ (b) r共t兲 苷 具 1, 2t典 y 7. 18.6833 冊 冉 1 1 共13 3兾2 8兲 31. ( 2 ln 2, 1兾s2 ); approaches 0 35. 4 r(4) 0 1 27 冉 13. r共t共s兲兲 苷 r(4.5)-r(4) 0.5 1 5. 2 3 4 si 1 s j 5 s k s29 s29 s29 15. 共3 sin 1, 4, 3 cos 1兲 17. (a) 具 1兾s10 , (3兾s10 )sin t, (3兾s10 ) cos t 典, 具0, cos t, sin t典 (b) 103 1 1 19. (a) 2t 具 具 1 e 2t, s2 e t, s2 e t 典 s2 e t, e 2t, 1 典 , 2t e 1 e 1 (b) s2 e 2t兾共e 2t 1兲2 1 19 4 21. 6t 2兾共9t 4 4t 2兲3兾2 23. 25 25. 7 s14 2 6 3兾2 x 27. 12x 兾共1 16x 兲 29. e x 2 兾关1 共xe x e x 兲2 兴 3兾2 r(4.2)-r(4) 0.2 C PAGE 860 3. e e1 11. 42 1. 10s10 9. 1.2780 x 1 N 4 _4 _1 (_3, 2) 37. rª(_1) (t) r(_1) 0.6 5 0 x z 5. (a), (c) (b) r共t兲 苷 cos t i 2 sin t j y 0 _5 0 2 ” œ„ , œ„2 ’ 2 50 y 100 0 250 x 500 _5 π rª” 4 ’ 0 π r” 4 ’ x 0 5 t 39. a is y 苷 f 共x兲, b is y 苷 共x兲 41. 共t兲 苷 6s4 cos 2 t 12 cos t 13 共17 12 cos t兲 3兾2 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA116-125.qk_97909_Ans_Ans_pA116-125 10/18/10 10:18 AM Page 119 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 11. s2 i e t j et k, e t j et k, e t et 13. e t 关共cos t sin t兲 i 共sin t cos t兲 j 共t 1兲 k兴, k(t) e t 关2 sin t i 2 cos t j 共t 2兲 k兴, e tst 2 2t 3 1 15. v共t兲 苷 t i 2t j k, r共t兲 苷 ( 2 t 2 1兲 i t 2 j t k 1 3 1 1 17. (a) r共t兲 苷 ( 3 t t ) i 共t sin t 1兲 j ( 4 4 cos 2t) k (b) integer multiples of 2 0 2π 4π 6π t 43. 6t 2兾共4 t 2 9t 4 兲3兾2 z 45. 1兾(s2e t) 47. 具 3 , 3 , 3 典, 具 3 , 3 , 3 典, 具 3 , 3 , 3 典 49. y 苷 6x , x 6y 苷 6 5 2 81 5 2 16 51. ( x 2 ) y 2 苷 4 , x 2 ( y 3 ) 苷 9 2 2 1 1 2 2 2 1 2 7.5 0.6 0.4 0.2 0 _10 200 x 5 19. 21. 23. 25. 29. 31. 33. 2.5 0 0 y _200 10 t苷4 r共t兲 苷 t i t j 52 t 2 k, v共t兲 苷 s25t 2 2 (a) ⬇3535 m (b) ⬇1531 m (c) 200 m兾s 30 m兾s 27. ⬇10.2, ⬇79.8 13.0 36.0, 55.4 85.5 共250, 50, 0兲; 10s93 ⬇ 96.4 ft兾s (a) 16 m (b) ⬇23.6 upstream ⱍ ⱍ 12 20 5 53. 共1, 3, 1兲 55. 2x y 4z 苷 7, 6x 8y z 苷 3 63. 2兾共t 4 4t 2 1兲 65. 2.07 1010 Å ⬇ 2 m EXERCISES 13.4 N PAGE 870 40 _12 _4 1. (a) 1.8 i 3.8 j 0.7 k, 2.0 i 2.4 j 0.6 k, 2.8 i 1.8 j 0.3 k, 2.8 i 0.8 j 0.4 k (b) 2.4 i 0.8 j 0.5 k, 2.58 3. v共t兲 苷 具t, 1典 a共t兲 苷 具 1, 0典 v共t兲 苷 st 2 1 35. The path is contained in a circle that lies in a plane perpendicular to c with center on a line through the origin in the direction of c. 37. 6t, 6 39. 0, 1 41. e t et, s2 43. 4.5 cm兾s2, 9.0 cm兾s2 45. t 苷 1 y v(2) (_2, 2) ⱍ 40 0 0 ⱍ A119 a(2) CHAPTER 13 REVIEW N PAGE 873 0 x True-False Quiz 1. True 3. False 9. True 11. False 5. v共t兲 苷 3 sin t i 2 cos t j ⱍ Exercises 1. (a) y a共t兲 苷 3 cos t i 2 sin t j v共t兲 苷 s5 sin 2 t 4 v” π3 ’ (0, 2) ⱍ 3 ” 2 , œ„ 3’ a” π3 ’ 5. False 13. True 7. False z (3, 0) x 0 (0, 1, 0) y x 7. v共t兲 苷 i 2t j z a共t兲 苷 2 j v共t兲 苷 s1 4t 2 ⱍ ⱍ a(1) (1, 1, 2) v(1) y x 9. 具2t 1, 2t 1, 3t 2 典 , 具2, 2, 6t典 , s9t 4 8t 2 2 (2, 1, 0) (b) r 共t兲 苷 i sin t j cos t k, r 共t兲 苷 2 cos t j 2 sin t k t 2 3. r共t兲 苷 4 cos t i 4 sin t j 共5 4 cos t兲 k, 0 1 5. 3 i 共2兾 2兲 j 共2兾 兲 k 7. 86.631 9. 兾2 11. (a) 具t 2, t, 1典兾st 4 t 2 1 (b) 具t 3 2t, 1 t 4, 2t 3 t典兾st 8 5t 6 6t 4 5t 2 1 (c) st 8 5t 6 6t 4 5t 2 1兾共t 4 t 2 1兲2 13. 12兾17 3兾2 15. x 2y 2 苷 0 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA116-125.qk_97909_Ans_Ans_pA116-125 10/14/10 5:00 PM Page 120 A120 APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES 17. v共t兲 苷 共1 ln t兲 i j et k, ⱍ ⱍ 23. (a) v 苷 R共sin t i cos t j兲 PROBLEMS PLUS N ⱍ 17. 兵共x, y兲 1 x 1, 1 y 1其 v共t兲 苷 s2 2 ln t 共ln t兲2 e2t , a共t兲 苷 共1兾t兲 i et k 19. (a) About 3.8 ft above the ground, 60.8 ft from the athlete (b) ⬇21.4 ft (c) ⬇64.2 ft from the athlete 21. (c) 2et vd et R y 1 _1 (c) a 苷 r PAGE 876 ⱍ 19. 兵共x, y兲 y x 2, x 苷 1其 y (b) ⬇7.6 (c) ⬇2.13 ft to the right of the table’s edge 5. 56 7. r共u, v兲 苷 c u a v b where a 苷 具a1, a 2 , a 3 典, b 苷 具b1, b 2 , b 3 典, c 苷 具 c1, c 2 , c 3 典 y=≈ _1 CHAPTER 14 EXERCISES 14.1 x _1 1. (a) 90, v02兾共2t兲 3. (a) ⬇0.94 ft to the right of the table’s edge, ⬇15 ft兾s ⱍ 21. 兵共x, y, z兲 x 2 y 2 z 2 1其 N 1 0 2 0 x 1 z PAGE 888 1. (a) 27; a temperature of 15C with wind blowing at 0 40 km兾h feels equivalent to about 27C without wind. (b) When the temperature is 20C, what wind speed gives a wind chill of 30C ? 20 km兾h (c) With a wind speed of 20 km兾h, what temperature gives a wind chill of 49C ? 35C (d) A function of wind speed that gives wind-chill values when the temperature is 5C (e) A function of temperature that gives wind-chill values when the wind speed is 50 km兾h 3. ⬇94.2; the manufacturer’s yearly production is valued at $94.2 million when 120,000 labor hours are spent and $20 million in capital is invested. 5. (a) ⬇20.5; the surface area of a person 70 inches tall who weighs 160 pounds is approximately 20.5 square feet. 7. (a) 25; a 40-knot wind blowing in the open sea for 15 h will create waves about 25 ft high. (b) f 共30, t兲 is a function of t giving the wave heights produced by 30-knot winds blowing for t hours. (c) f 共v, 30兲 is a function of v giving the wave heights produced by winds of speed v blowing for 30 hours. 9. (a) 1 (b) ⺢ 2 (c) 关1, 1兴 11. (a) 3 (b) 兵共x, y, z兲 x 2 y 2 z 2 4, x 0, y 0, z 0其, interior of a sphere of radius 2, center the origin, in the first octant 13. 兵共x, y兲 y 2x其 y y x 23. z 苷 1 y, plane parallel to x-axis z (0, 0, 1) 0 (0, _1, 0) x y 25. 4x 5y z 苷 10, plane z (0, 0, 10) ⱍ ⱍ 0 (0, 2, 0) (2.5, 0, 0) y x 0 x 27. z 苷 y 2 1 , parabolic cylinder y=2x 15. 兵共x, y兲 ⱍ 1 9 x2 y2 1其, 共, ln 9兴 z y 1 9 ≈+¥=1 0 x x y Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA116-125.qk_97909_Ans_Ans_pA116-125 10/14/10 5:00 PM Page 121 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 29. z 苷 9 x 2 9y 2, 51. x 2 9y 2 苷 k z elliptic paraboloid A121 z y (0, 0, 9) z=4 2 1 x 4 0 (0, 1, 0) (3, 0, 0) 3 x z=3 y z=2 z=1 31. z 苷 s4 4x 2 y 2 , z top half of ellipsoid y (0, 0, 2) x 53. (0, 2, 0) (1, 0, 0) y x 33. ⬇56, ⬇35 39. 35. 11C, 19.5C 41. z y 0 x 37. Steep; nearly flat 55. z 5 z 0 14 _2 y x 0 2 2 0 _2 x 57. y x y 1.0 z 0.5 43. 共 y 2x兲 苷 k 45. y 苷 sx k 2 0.0 y y _4 y 0 x 2 1 x 0 _1 43 2 1 0 _2 1 234 47. y 苷 kex 49. y 2 x 2 苷 k 2 y 1 2 20 2 1 0 z _20 0 0 _2 _1 x 0 1 2 _3 (a) C (b) II 61. (a) F (b) I (a) B (b) VI 65. Family of parallel planes Family of circular cylinders with axis the x-axis 共k 0兲 (a) Shift the graph of f upward 2 units (b) Stretch the graph of f vertically by a factor of 2 (c) Reflect the graph of f about the xy-plane (d) Reflect the graph of f about the xy-plane and then shift it upward 2 units 59. 63. 67. 69. 3 0 3 _4 x 71. y 3 0 4 4 x _40 _5 y 0 5 5 0x _5 f appears to have a maximum value of about 15. There are two local maximum points but no local minimum point. Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA116-125.qk_97909_Ans_Ans_pA116-125 10/14/10 5:00 PM Page 122 A122 73. APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES 5. (a) Positive (b) Negative 7. (a) Positive (b) Negative 9. c 苷 f, b 苷 fx, a 苷 fy 11. fx 共1, 2兲 苷 8 苷 slope of C1, fy共1, 2兲 苷 4 苷 slope of C2 10 5 z 0 z _5 _10 2 z 16 16 x 0 0 _2 2 _2 The function values approach 0 as x, y become large; as 共x, y兲 approaches the origin, f approaches or 0, depending on the direction of approach. 75. If c 苷 0, the graph is a cylindrical surface. For c 0, the level curves are ellipses. The graph curves upward as we leave the origin, and the steepness increases as c increases. For c 0, the level curves are hyperbolas. The graph curves upward in the y-direction and downward, approaching the xy-plane, in the x-direction giving a saddle-shaped appearance near (0, 0, 1). 77. c 苷 2, 0, 2 79. (b) y 苷 0.75x 0.01 C¡ 0 y x (1, 2) 0 2 _2 ⱍ ⱍ ⱍ 2 _2 y 20 z 0 _20 2 _2 0 x ⱍ 2 _2 0 y fx 共x, y兲 苷 2xy 3 35. 兵共x, y, z兲 x 2 y 2 z 2 1其 39. 0 0 0 f 共x, y兲 苷 x 2 y 3 bers along different lines. 25. h共x, y兲 苷 共2 x 3y 6兲 2 s2x 3y 6 ; 兵共x, y兲 2x 3y 6其 27. Along the line y 苷 x 29. ⺢ 2 31. 兵共x, y兲 x 2 y 2 苷 1其 37. 兵共x, y兲 共x, y兲 苷 共0, 0兲其 (1, 2) _20 1. Nothing; if f is continuous, f 共3, 1兲 苷 6 3. 2 7. 7 9. Does not exist 11. Does not exist 5. 1 13. 0 15. Does not exist 17. 2 19. s3 21. Does not exist 23. The graph shows that the function approaches different num- 33. 兵共x, y兲 x 2 y 2 4其 y x 20 z 5 2 ⱍ 4 2 13. PAGE 899 N C™ 0 4 2 x EXERCISES 14.2 (1, 2, 8) (1, 2, 8) y 41. 1 43. 40 z 2 1 z 0 _1 y 0 2 2 0x x EXERCISES 14.3 PAGE 911 1. (a) The rate of change of temperature as longitude varies, with latitude and time fixed; the rate of change as only latitude varies; the rate of change as only time varies. (b) Positive, negative, positive 3. (a) fT 共15, 30兲 ⬇ 1.3; for a temperature of 15C and wind speed of 30 km兾h, the wind-chill index rises by 1.3C for each degree the temperature increases. fv 共15, 30兲 ⬇ 0.15; for a temperature of 15C and wind speed of 30 km兾h, the wind-chill index decreases by 0.15C for each km兾h the wind speed increases. (b) Positive, negative (c) 0 0 0 2 _2 y fy 共x, y兲 苷 3x 2 y 2 f is continuous on ⺢ 2 N 2 0 _2 _2 _2 20 fx 共x, y兲 苷 3y, fy 共x, y兲 苷 5y 4 3x fx 共x, t兲 苷 e t sin x, ft 共x, t兲 苷 et cos x z兾x 苷 20共2x 3y兲 9, z兾y 苷 30共2x 3y兲 9 fx 共x, y兲 苷 1兾y, fy 共x, y兲 苷 x兾y 2 共ad bc兲y 共bc ad兲x 23. fx 共x, y兲 苷 , fy 共x, y兲 苷 共cx dy兲2 共cx dy兲2 2 3 4 25. tu共u, v兲 苷 10uv共u v v 兲 , tv共u, v兲 苷 5共u 2 3v 2兲共u 2v v 3 兲 4 q2 2pq 27. Rp共 p, q兲 苷 , R q 共 p, q兲 苷 1 p 2q 4 1 p 2q 4 29. Fx共x, y兲 苷 cos共e x 兲, Fy 共x, y兲 苷 cos共e y兲 31. fx 苷 z 10xy 3z 4, fy 苷 15x 2 y 2z 4, fz 苷 x 20x 2 y 3z 3 33. w兾x 苷 1兾共x 2y 3z兲, w兾y 苷 2兾共x 2y 3z兲, w兾z 苷 3兾共x 2y 3z兲 15. 17. 19. 21. Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA116-125.qk_97909_Ans_Ans_pA116-125 10/14/10 5:00 PM Page 123 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 35. u兾x 苷 y sin1 共 yz兲, u兾y 苷 x sin1 共 yz兲 xyz兾s1 y 2 z 2, u兾z 苷 xy 兾s1 y z 37. h x 苷 2xy cos共z兾t兲, h y 苷 x 2 cos共z兾t兲, h z 苷 共x 2 y兾t兲 sin共z兾t兲, h t 苷 共x 2 yz兾t 2 兲 sin共z兾t兲 39. u兾xi 苷 xi兾sx 12 x 22 x n2 1 1 41. 5 43. 4 45. fx 共x, y兲 苷 y 2 3x 2 y , fy 共x, y兲 苷 2xy x 3 z x z 2y 47. 苷 , 苷 x 3z y 3z z z yz xz 49. 苷 z , 苷 z x e xy y e xy 51. (a) f 共x兲, t共 y兲 (b) f 共x y兲, f 共x y兲 53. fxx 苷 6xy 5 24x 2 y, fxy 苷 15x 2 y 4 8x 3 苷 fyx , fyy 苷 20x 3 y 3 55. wuu 苷 v 2兾共u 2 v 2 兲3兾2, wuv 苷 uv兾共u 2 v 2 兲3兾2 苷 wvu, wvv 苷 u 2兾共u 2 v 2 兲3兾2 57. zxx 苷 2x兾共1 x 2 兲 2, zxy 苷 0 苷 zyx , zyy 苷 2y兾共1 y 2 兲 2 2 63. 24xy 2 6y, 24x 2 y 6x 65. 共2x 2 y 2z 5 6xyz 3 2z兲e xyz 67. e r 共2 sin cos r sin 兲 69. 4兾共 y 2z兲 3 , 0 71. 6yz 2 73. ⬇12.2, ⬇16.8, ⬇23.25 83. R 2兾R 21 T V nb P 2n 2a nRT 87. 苷 , 苷 P nR V V3 共V nb兲2 93. No 95. x 苷 1 t, y 苷 2, z 苷 2 2t 99. 2 101. (a) 2 2 2 0.2 _0.2 _1 y 0 1 0 1 _1 x x 4y 4x 2y 3 y 5 x 5 4x 3y 2 xy 4 , fy共x, y兲 苷 2 2 2 共x y 兲 共x 2 y 2 兲2 (e) No, since fxy and fyx are not continuous. (b) fx 共x, y兲 苷 EXERCISES 14.4 N PAGE 922 1. z 苷 7x 6y 5 5. x y z 苷 0 7. 3. x y 2z 苷 0 3. 关共x兾t兲 y sin t兴兾s1 x 2 y 2 5. e y兾z 关2t 共x兾z兲 共2xy兾z 2 兲兴 7. z兾s 苷 2xy 3 cos t 3x 2 y 2 sin t, z兾t 苷 2sxy 3 sin t 3sx 2 y 2 cos t 9. z兾s 苷 t 2 cos cos 2st sin sin , z兾t 苷 2st cos cos s 2 sin sin 11. z t 13. 17. u t 冉 z 苷 e r t cos s 冉 _1 0 11. 6x 4y 23 23. 25. 27. 29. 31. 37. 39. 0 0 y _5 0 2 2 21. 3 7 冊 w w r w s w t 苷 , x r x s x t x w w r w s w t 苷 y r y s y t y 21. 1582, 3164, 700 23. 2, 2 19. 2x y sin x cos x 2y 1 x 4 y 2 y 2 x 4 y 4 2xy 29. x 2 2xy 2x 5y 3 x 2y yz xz , 31. , 33. z 3z 3z e xy e z xy 35. 2C兾s 37. ⬇ 0.33 m兾s per minute 39. (a) 6 m3兾s (b) 10 m 2兾s (c) 0 m兾s 41. ⬇ 0.27 L兾s 43. 1兾 (12 s3 ) rad兾s 45. (a) z兾r 苷 共z兾x兲 cos 共z兾y兲 sin , z兾 苷 共z兾x兲r sin 共z兾y兲r cos 51. 4rs 2z兾x 2 共4r 2 4s 2 兲2z兾x y 4rs 2z兾y 2 2 z兾y 5 144 5 , 965 , 144 27. 13. x y 1 9 6 7 2 9 2 3 N PAGE 943 x (b) 具2, 3典 (c) s3 32 9. (a) 具2xyz yz 3, x 2z xz 3, x 2 y 3xyz 2 典 (b) 具3, 2, 2典 (c) 25 y 15. 1 y x 27 y z; 6.9914 4T H 329; 129F dz 苷 2e 2x cos 2 t dx 2 e 2x sin 2 t dt dm 苷 5p 4q 3 dp 3p 5q 2 dq dR 苷 2 cos d 2 cos d 2 sin d z 苷 0.9225, dz 苷 0.9 33. 5.4 cm 2 35. 16 cm 3 ⬇0.0165mg; decrease 1 41. 2.3% 43. 1 苷 x, 2 苷 y 17 ⬇ 0.059 19. 6.3 1. ⬇ 0.08 mb兾km 3. ⬇ 0.778 5. 2 s3兾2 7. (a) f 共x, y兲 苷 具 2 cos共2x 3y兲, 3 cos共2x 3y兲 典 z 0 z 200 5 冊 s sin , ss 2 t 2 t 苷 e r s cos sin ss 2 t 2 62 15. 7, 2 u u x u y u u x u y 苷 , 苷 , r x r y r s x s y s u x u y 苷 x t y t EXERCISES 14.6 1 x 0 _10 PAGE 930 9. 400 10 N 1. 共2x y兲 cos t 共2y x兲e t 25. z 0 (c) 0, 0 EXERCISES 14.5 A123 11. 17. 23. 27. 29. 31. 33. 4 3s3 10 13. 8兾s10 15. 4兾s30 19. 2兾5 21. s65 , 具1, 8 典 25. 1, 具 3, 6, 2 典 1, 具0, 1典 (b) 具12, 92典 All points on the line y 苷 x 1 (a) 40兾(3 s3 ) (a) 32兾s3 (b) 具38, 6, 12典 (c) 2 s406 23 42 327 774 35. 13 39. 25 41. (a) x y z 苷 11 (b) x 3 苷 y 3 苷 z 5 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA116-125.qk_97909_Ans_Ans_pA116-125 10/14/10 5:00 PM Page 124 A124 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I x3 y2 z1 苷 苷 2 3 12 (b) x 苷 y 苷 z 1 49. 具2, 3典 , 2x 3y 苷 12 43. (a) 2x 3y 12z 苷 24 45. (a) x y z 苷 1 47. 41. (2, 1, s5 ), (2, 1, s5 ) 100 , 100 3 , 3 45. 8r 兾 (3s3 ) 47. 49. Cube, edge length c兾12 51. Square base of side 40 cm, height 20 cm 53. L 3兾 (3s3 ) 39. 2兾s3 (b) 43. 100 3 4 3 3 y EXERCISES 14.8 xy=6 2 Î f (3, 2) 2x+3y=12 z 1 (3, 2) 0 0 x N PAGE 963 1. ⬇59, 30 3. No maximum, minimum f 共1, 1兲 苷 f 共1, 1兲 苷 2 5. Maximum f 共0, 1兲 苷 1, minimum f 共2, 0兲 苷 4 7. Maximum f 共2, 2, 1兲 苷 9, minimum f 共2, 2, 1兲 苷 9 9. Maximum 2兾s3, minimum 2兾s3 11. Maximum s3, minimum 1 13. Maximum f ( 2 , 2 , 2 , 2 ) 苷 2, 1 _1 1 x 2 1 y 5 5 25 8 ) 63. x 苷 1 10t, y 苷 1 16t, z 苷 2 12t 67. If u 苷 具 a, b典 and v 苷 具c, d 典 , then afx bfy and c fx d fy are known, so we solve linear equations for fx and fy . EXERCISES 14.7 N PAGE 953 1. (a) f has a local minimum at (1, 1). (b) f has a saddle point at (1, 1). 3. Local minimum at (1, 1), saddle point at (0, 0) 1 2 1 5. Minimum f ( 3, 3 ) 苷 3 7. Saddle points at 共1, 1兲, 共1, 1兲 9. Maximum f 共0, 0兲 苷 2, minimum f 共0, 4兲 苷 30, saddle points at 共2, 2兲, 共2, 2兲 11. Minimum f 共2, 1兲 苷 8, saddle point at 共0, 0兲 15. Minimum f 共0, 0兲 苷 0, saddle points at 共1, 0兲 13. None 17. Minima f 共0, 1兲 苷 f 共, 1兲 苷 f 共2, 1兲 苷 1, saddle points at 共兾2, 0兲, 共3兾2, 0兲 21. Minima f 共1, 1兲 苷 3, f 共1, 1兲 苷 3 23. Maximum f 共兾3, 兾3兲 苷 3 s3兾2, minimum f 共5兾3, 5兾3兲 苷 3 s3兾2, saddle point at 共, 兲 25. Minima f 共0, 0.794兲 ⬇ 1.191, f 共1.592, 1.267兲 ⬇ 1.310, saddle points 共0.720, 0.259兲, lowest points 共1.592, 1.267, 1.310兲 27. Maximum f 共0.170, 1.215兲 ⬇ 3.197, minima f 共1.301, 0.549兲 ⬇ 3.145, f 共1.131, 0.549兲 ⬇ 0.701, saddle points 共1.301, 1.215兲, 共0.170, 0.549兲, 共1.131, 1.215兲, no highest or lowest point 29. Maximum f 共0, 2兲 苷 4, minimum f 共1, 0兲 苷 1 31. Maximum f 共1, 1兲 苷 7, minimum f 共0, 0兲 苷 4 33. Maximum f 共3, 0兲 苷 83, minimum f 共1, 1兲 苷 0 35. Maximum f 共1, 0兲 苷 2, minimum f 共1, 0兲 苷 2 37. 1 1 minimum f ( , , , 12 ) 苷 2 2 59. (4 , 4 , 55. No 1 1 2 (_1, 0, 0) 1 2 15. Maximum f (1, s2, s2 ) 苷 1 2 s2, minimum f (1, s2, s2 ) 苷 1 2 s2 3 1 17. Maximum 2 , minimum 2 19. Maximum f (3兾s2 , 3兾s2 ) 苷 9 12s2 , minimum f 共2, 2兲 苷 8 21. Maximum f (1兾s2, 1兾(2 s2 )) 苷 e 1兾4, minimum f (1兾s2, 1兾(2 s2 )) 苷 e1兾4 29– 41. See Exercises 39–53 in Section 14.7. 1 1 1 43. Nearest ( 2 , 2 , 2 ), farthest 共1, 1, 2兲 45. Maximum ⬇9.7938, minimum ⬇5.3506 47. (a) c兾n (b) When x1 苷 x2 苷 苷 xn CHAPTER 14 REVIEW N PAGE 967 True-False Quiz 1. True 3. False 11. True 5. False Exercises 1. 兵共x, y兲 y x 1其 ⱍ 7. True 3. 9. False z 1 y _1 x 1 x y _1 y=_x-1 5. y 7. y 2 (1, 2, 0) 1 0 0 1 2 2 34 5 1 x _1 z _2 _3 _1 0 x 1 4 2y _2 0 1 2 x Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA116-125.qk_97909_Ans_Ans_pA116-125 10/14/10 5:00 PM Page 125 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 2 9. 3 11. (a) ⬇3.5C兾m , 3.0C兾m (b) ⬇ 0.35C兾m by Equation 14.6.9 (Definition 14.6.2 gives ⬇1.1C兾m .) (c) 0.25 13. fx 苷 32xy共5y 3 2x 2y兲7, fy 苷 共16x 2 120y 2 兲共5y 3 2x 2 y兲7 15. F 苷 17. 9 ln 2 23. 1 2 19. (s3 1) 121 1 5 2 z 4 2 3 2 2 2 ln共 2 2 兲, F 苷 2 2 2 2 usw uv , Sw 苷 1 v 2w 2sw 共1 v 2w兲 19. f xx 苷 24x, f xy 苷 2y 苷 f yx, f yy 苷 2x 21. f xx 苷 k共k 1兲x k2 y lz m, f xy 苷 klx k1 y l1z m 苷 f yx, f xz 苷 kmx k1 y lz m1 苷 f zx, f yy 苷 l共l 1兲x k y l2z m, f yz 苷 lmx k y l1z m1 苷 f zy, f zz 苷 m共m 1兲x k y lz m2 y2 z1 x1 25. (a) z 苷 8x 4y 1 (b) 苷 苷 8 4 1 x2 y1 z1 27. (a) 2x 2y 3z 苷 3 (b) 苷 苷 4 4 6 29. (a) x 2y 5z 苷 0 (b) x 苷 2 t, y 苷 1 2t, z 苷 5t 1 1 31. (2, 2 , 1), (2, 2 , 1) 24 32 33. 60x 5 y 5 z 120; 38.656 35. 2xy 3共1 6p兲 3x 2 y 2共 pe p e p兲 4z 3共 p cos p sin p兲 37. 47, 108 4 43. 具 2xe yz , x 2 z 2e yz , 2x 2 yze yz 典 45. 5 9 5 47. s145兾2, 具4, 2 典 49. ⬇ 8 knot兾mi 51. Minimum f 共4, 1兲 苷 11 53. Maximum f 共1, 1兲 苷 1; saddle points (0, 0), (0, 3), (3, 0) 55. Maximum f 共1, 2兲 苷 4, minimum f 共2, 4兲 苷 64 57. Maximum f 共1, 0兲 苷 2, minima f 共1, 1兲 苷 3, saddle points 共1, 1兲, 共1, 0兲 59. Maximum f (s2兾3, 1兾s3 ) 苷 2兾(3 s3 ), minimum f (s2兾3, 1兾s3 ) 苷 2兾(3 s3 ) 61. Maximum 1, minimum 1 63. (31兾4, 31兾4s2, 31兾4 ), (31兾4, 31兾4s2, 31兾4 ) 65. P(2 s3 ), P(3 s3 )兾6, P(2 s3 3)兾3 0 17. Su 苷 arctan (v sw ), Sv 苷 2 2 PROBLEMS PLUS N y x 25. 51 27. 33. 21e 57 166 27 31. z 0 0 y 5 discontinuity at the origin. EXERCISES 15.3 1. 32 11. (a) 3. N 3 10 PAGE 995 1 3 5. sin 1 7. y y D D 0 x 0 x ⱍ (b) Yes ⱍ 15. 2 sx x01 xsxsx y dy dx x14 xx2 y dy dx苷 x1 xyy2 y dx dy 苷 94 2 17. 共1 cos 1兲 27. 6 37. N 9. 4 3 (b) 29. 128 15 19. 11 3 31. 1 3 21. 0 23. 17 60 33. 0, 1.213; 0.713 25. 31 8 35. z (0, 0, 1) PAGE 981 0 (0, 1, 0) (1, 0, 0) y x PAGE 987 1. 500y , 3x 3. 222 5. 32共e 1兲 21 31 9. 2 ln 2 11. 30 13. 15. 0 2 0 x 1 1 35. 6 37. 0 39. Fubini’s Theorem does not apply. The integrand has an infinite 1. (a) 288 (b) 144 3. (a) 0.990 (b) 1.151 5. (a) 4 (b) 8 7. U V L 9. (a) ⬇248 (b) ⬇15.5 11. 60 13. 3 15. 1.141606, 1.143191, 1.143535, 1.143617, 1.143637, 1.143642 EXERCISES 15.2 64 3 2 1 2 N 29. 2 13. Type I: D 苷 兵共x, y兲 0 x 1, 0 y x其, type II: D 苷 兵共x, y兲 0 y 1, y x 1其; 13 PAGE 971 CHAPTER 15 EXERCISES 15.1 1 1 2 3. (a) x 苷 w兾3, base 苷 w兾3 1 1. L2W 2, 4 L2W 2 7. s3兾2, 3兾s2 3 21. 2 e 6 A125 4 7. 18 39. 13,984,735,616兾14,549,535 41. 兾2 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 64 3 97909_Ans_Ans_pA126-134.qk_97909_Ans_Ans_pA126-134 10/14/10 5:11 PM Page 126 A126 43. ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I x01 xx1 f 共x, y兲 dy dx 23. a 4兾16, a 4兾16; a兾2, a兾 2 y (0, 1) y=x 0 45. x01 x0cos 1 y f 共x, y兲 dx dy x y 1 y=cos x or x=cos_1y 0 47. x0ln 2 xe2 f 共x, y兲 dx dy y y 33. (a) x π 2 y=ln x or x=e† 0 1 1. 5. 3兾2 4 0 0 x x N 1 f 共r cos , r sin 兲r dr d 3π ¨= 4 π ¨= 4 1 1 共x1兲兾2 0 x x 3. EXERCISES 15.7 27 1. 4 65 13. 28 _1 0 ] (b) ⬇1.8616 f 共x, y兲 dy dx 3兾4 23. (a) s1y 2 0 x x x 25. 0.985 27. 1 9. 17. 16兾3 1 60 x 0 7. 3 5 3 5. 15. 1 0 PAGE 1025 N 16 15 3. R _2 [ ln (11s5 3s70 )兾(3s5 s70 ) 23. 共兾6兲(101 s101 1) 15 16 2 2 PAGE 1002 y 17. 8 s14 19. 3.3213 45 x 2 49. 6 共e 9 1兲 51. 3 ln 9 53. 3 (2 s2 1) 55. 1 3 57. 共兾16兲e1兾16 xxQ e共x y 兲 dA 兾16 59. 4 63. 9 3 65. a 2b 2 ab 2 67. a 2b EXERCISES 15.4 PAGE 1016 N 2 x=2 2 disk with radius 10 mi centered at the center of the city 8 (b) 200k兾3 ⬇ 209k, 200(兾2 9 )k ⬇ 136k, on the edge 1. 15 s26 3. 3 s14 5. 12 sin1 ( 3 ) 7. 共兾6兲(17 s17 5 s5 ) 9. 共2兾3兲(2 s2 1) 11. a 2共 2兲 13. 13.9783 15. (a) ⬇1.83 y=0 1 冊 xxD k [1 201 s共x x0 兲2 共 y y0 兲2 ] dA, where D is the EXERCISES 15.6 ln 2 1 冉 16384 s2 ,0 , 10395 5 5 4 4 5 , Iy 苷 , I0 苷 Ix 苷 384 105 384 105 192 1 27. (a) 2 (b) 0.375 (c) 485 ⬇ 0.1042 0.2 29. (b) (i) e ⬇ 0.8187 (ii) 1 e1.8 e0.8 e1 ⬇ 0.3481 (c) 2, 5 31. (a) ⬇0.500 (b) ⬇0.632 25. m 苷 3兾64, 共x, y兲 苷 (1, 1) dz dy dx 19. 27 2 16 3 1 3 11. 9兾8 21. 8 15 (b) 1 4 z 1 1 2 x 2 0 1 y x 7. 3 9. 共兾4兲共cos 1 cos 9兲 3 11. 共兾2兲共1 e4 兲 13. 64 2 1250 2 s4x y兾2 x2 x04x xs4x f 共x, y, z兲 dz dy dx y兾2 4 s4y s4x y兾2 苷 x0 xs4y xs4x y兾2 f 共x, y, z兲 dz dx dy 1 s4y4z x044z xs4y4z f 共x, y, z兲 dx dy dz 苷 x1 s4y兾2 s4y4z xs4y4z f 共x, y, z兲 dx dz dy 苷 x04 xs4y兾2 2 4x 4z s4x 兾2 f 共x, y, z兲 dy dz dx 苷 x2 xs4x 兾2 x0 1 4x 4z s44z f 共x, y, z兲 dy dx dz 苷 x1 xs44z x0 s3 4 16 4 19. 3 21. 3 23. 3 a 3 3 2 25. 共2兾3兲[1 (1兾s2 )] 27. 共8兾3兲(64 24 s3 ) 1 29. 2 共1 cos 9兲 31. 2s2兾3 33. 4.5951 37. 2兾共a b兲 41. (a) s 兾4 (b) s 兾2 EXERCISES 15.5 N 39. 2 2 2 2 2 2 2 15 16 2 2 2 2 2 2 2 x2 xx4 x02y兾2 f 共x, y, z兲 dz dy dx sy x02y兾2 f 共x, y, z兲 dz dx dy 苷 x04 xsy sy f 共x, y, z兲 dx dy dz 苷 x02 x042z xsy 4 2y兾2 sy xsy f 共x, y, z兲 dx dz dy 苷 x0 x0 2 x02x 兾2 xx42z f 共x, y, z兲 dy dz dx 苷 x2 s42z xx42z f 共x, y, z兲 dy dx dz 苷 x02 xs42z 31. 1. 285 C 3. 42k, (2, ) 5. 6, ( , ) 7. k, (0, ) 3 9. L兾4, 共L兾2, 16兾共9兲兲 11. ( 8 , 3兾16) 13. 共0, 45兾共14兲兲 15. 共2a兾5, 2a兾5兲 if vertex is (0, 0) and sides are along positive axes 64 8 88 17. 315 k, 105 k, 315 k 3 4 3 2 8 15 4 7 19. 7 ka 6兾180, 7 ka 6兾180, 7 ka 6兾90 if vertex is 共0, 0兲 and sides are along positive axes 21. bh 3兾3, b 3h兾3; b兾s3, h兾s3 2 2 PAGE 1012 85 28 2 2 17. 35. 1800 ft 3 2 29. 15. 兾12 2 2 2 2 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA126-134.qk_97909_Ans_Ans_pA126-134 10/14/10 5:11 PM Page 127 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I x01 xsx1 x01y f 共x, y, z兲 dz dy dx 苷 x01 x0y x01y f 共x, y, z兲 dz dx dy 苷 x01 x01z x0y f 共x, y, z兲 dx dy dz 苷 x01 x01y x0y f 共x, y, z兲 dx dz dy 1z 1z f 共x, y, z兲 dy dz dx 苷 x01 x0共1z兲 xsx f 共x, y, z兲 dy dx dz 苷 x01 x01sx xsx 2 33. 2 15. A127 4 z 2 2 x01 xy1 x0y f 共x, y, z兲 dz dx dy 苷 x01 x0x x0y f 共x, y, z兲 dz dy dx 苷 x01 xz1 xy1 f 共x, y, z兲 dx dy dz 苷 x01 x0y xy1 f 共x, y, z兲 dx dz dy 苷 x01 x0x xzx f 共x, y, z兲 dy dz dx 苷 x01 xz1 xzx f 共x, y, z兲 dy dx dz 35. 37. 64 33 571 , ( 358 553 , 79 , 553 ) 79 30 39. x y 41. a , 共7a兾12, 7a兾12, 7a兾12兲 5 2 47. (a) m 苷 8 128 4 384 19. 3 15 21. 2兾5 23. 3 (s2 1) (a) 162 (b) 共0, 0, 15兲 Ka 2兾8, 共0, 0, 2a兾3兲 29. 0 (a) xxxC h共P兲t共P兲 dV, where C is the cone (b) ⬇3.1 1019 ft-lb 45. 2 kha 4 43. Ix 苷 Iy 苷 Iz 苷 3 kL5 17. 25. 27. 31. 1 1 x1 xx1 x01y sx 2 y 2 dz dy dx 2 (b) 共x, y, z兲, where 1 x 苷 共1兾m兲 x1 xx1 x01y x sx 2 y 2 dz dy dx 2 1 xx1 y 苷 共1兾m兲 x1 x y sx 2 y 2 dz dy dx z 苷 共1兾m兲 x x x zsx 2 y 2 dz dy dx 1 (c) x1 xx1 x 共x y 2 兲3兾2 dz dy dx 2 49. (a) (b) (c) 冉 3 32 1y 2 0 1 1 1y 1 x 2 0 1y 2 0 11 24 28 30 128 45 208 , , 9 44 45 220 135 660 1 240 EXERCISES 15.9 冊 (b) z z π π ”6, 3 , 6 ’ 0 π 6 6 (b) (c) 53. L3兾8 55. (a) The region bounded by the ellipsoid x 2 2y 2 3z 2 苷 1 (b) 4 s6 兾45 51. (a) 1 64 x 1. (a) π 3 z π ”2, _ 2 , 1’ π _2 y 冉 冊 z 2 4 π 3 ”3, 2 , 4 ’ 冊 11. 1 0 π 3π y 3 3s3 3s2 3s2 , , 3s3 0, , 2 2 2 2 3. (a) 共2, 3兾2, 兾2兲 (b) 共2, 3兾4, 3兾4兲 1 1 5. Half-cone 7. Sphere, radius 2 , center (0, 2, 0) 2 2 2 2 2 9. (a) cos 苷 sin (b) 共sin cos cos2 兲 苷 9 (b) z y 3 0 冉 PAGE 1031 N 3π 4 π 2 1 5760 x EXERCISES 15.8 PAGE 1037 1. (a) 共68 15兲 1 8 N ∏=4 0 y _2 x x π π ”4, 3 , _2’ ˙= 3 ∏=2 (2, 2s3 , 2) 3. (a) (s2 , 3兾4, 1) (b) 共4, 2兾3, 3兲 5. Vertical half-plane through the z-axis 7. Circular paraboloid 9. (a) z 2 苷 1 r cos r 2 (b) z 苷 r 2 cos 2 11. y 共0, 2, 1兲 x 13. z z 1 z=1 x y ˙= 2 x 3π 4 y ∏=1 2 13. Cylindrical coordinates: 6 r 7, 0 2, 0 z 20 15. 0 兾4, 0 cos Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA126-134.qk_97909_Ans_Ans_pA126-134 10/14/10 5:11 PM Page 128 A128 17. ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 共9兾4兲 (2 s3 ) z 3 45. (a) 47. 1 15 1. 30 x 3. 13. abc y (c) 1 45 sy x01 x01z xsy f 共x, y, z兲 dx dy dz PROBLEMS PLUS π 6 19. 1 3 (b) 冉 1 2 N 49. ln 2 51. 0 PAGE 1053 sin 1 2 8 3 9s3 冊 7. (b) 0.90 x0兾2 x03 x02 f 共r cos , r sin , z兲 r dz dr d 21. 312,500 兾7 23. 1688兾15 25. 兾8 27. (s3 1) a 3兾3 29. (a) 10 7 31. (a) (0, 0, 12) (b) 11K兾960 33. (a) (0, 0, 8 a) (b) (0, 0, 2.1) (b) 4Ka 5兾15 1 35. 3 (2 s2 ), (0, 0, 3兾 8(2 s2 ) ) 37. 5兾6 39. (4 s2 5 )兾15 41. 4096兾21 43. 45. 136兾99 3 [ ] CHAPTER 16 EXERCISES 16.1 N 1. PAGE 1061 y 2 1 _2 0 _1 x 1 _1 EXERCISES 15.10 PAGE 1047 N 3. 1. 16 3. sin cos 5. 0 7. The parallelogram with vertices (0, 0), (6, 3), (12, 1), (6, 2) 9. The region bounded by the line y 苷 1 , the y-axis, and y 苷 sx 1 1 11. x 苷 3 共v u兲 , y 苷 3 共u 2v兲 is one possible transformation, where S 苷 兵共u, v兲 1 u 1, 1 v 3其 13. x 苷 u cos v, y 苷 u sin v is one possible transformation, where S 苷 兵共u, v兲 1 u s2, 0 v 兾2 其 15. 3 17. 6 19. 2 ln 3 4 21. (a) 3 abc (b) 1.083 10 12 km 3 (c) 154 共a 2 b 2 兲abck 3 8 1 23. 5 ln 8 25. 2 sin 1 27. e e 2 y 2 2 ⱍ _2 ⱍ CHAPTER 15 REVIEW True-False Quiz 1. True 3. True N 2 x _2 5. y PAGE 1049 0 5. True 7. True x 9. False Exercises 1 2 1. ⬇64.0 3. 4e 2 4e 3 5. 2 sin 1 7. 3 4 9. x0 x2 f 共r cos , r sin 兲 r dr d 11. The region inside the loop of the four-leaved rose r 苷 sin 2 in the first quadrant 1 1 7 1 13. 2 sin 1 15. 2 e 6 2 17. 4 ln 2 19. 8 81 64 21. 81兾5 23. 2 25. 兾96 27. 15 2 29. 176 31. 3 33. 2ma 3兾9 1 1 8 35. (a) 4 (b) ( 3 , 15 ) (c) Ix 苷 121 , Iy 苷 241 ; y 苷 1兾s3, x 苷 1兾s6 37. (a) 共0, 0, h兾4兲 (b) a 4h兾10 486 39. ln(s2 s3 ) s2兾3 41. 5 43. 0.0512 7. 13. I 15. IV z x y x 11. IV 9. z y 17. III Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA126-134.qk_97909_Ans_Ans_pA126-134 10/14/10 5:11 PM Page 129 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 19. The line y 苷 2x 4.5 29. (a) 11 8 1兾e (b) A129 2.1 F{r(1)} 4.5 4.5 1 F ”r” œ„2 ’’ f 共x, y兲 苷 共xy 1兲e i x e j x i 23. f 共x, y, z兲 苷 sx 2 y 2 z 2 y z j k sx 2 y 2 z 2 sx 2 y 2 z 2 25. f 共x, y兲 苷 2x i j xy 21. F{r(0)} 0 4.5 2.1 _0.2 2 xy 31. 172,704 5,632,705 s2 共1 e14 兲 33. 2k, 共4兾, 0兲 35. (a) x 苷 共1兾m兲 xC x 共x, y, z兲 ds, y 苷 共1兾m兲 xC y 共x, y, z兲 ds, z 苷 共1兾m兲 xC z 共x, y, z兲 ds, where m 苷 xC 共x, y, z兲 ds y 2 (b) 共0, 0, 3兲 _6 _4 _2 0 4 _2 27. 6 x 37. Ix 苷 k ( 2 1 ), Iy 苷 k ( 12 23 ) 39. 2 2 41. 43. (a) 2ma i 6mbt j, 0 t 1 (b) 2ma mb 45. ⬇1.67 10 4 ft-lb 47. (b) Yes 51. ⬇22 J 2 9 2 7 3 2 4 EXERCISES 16.3 _4 _4 33. 共2.04, 1.03兲 31. II (b) y 苷 1兾x, x y 0 EXERCISES 16.4 1. 8 13. 4 y 苷 C兾x N 5 共145 3兾2 1兲 3. 1638.4 5. 8 7. 2 2 1 6 9. s5 11. 12 s14 共e 1兲 13. 5 共e 1兲 15. 17. (a) Positive (b) Negative 19. 45 6 21. 5 cos 1 sin 1 23. 1.9633 25. 15.0074 1 54 27. 3 3. N 2 3 PAGE 1089 5. 12 7. 1 15. 8e 48e 1 3 9. 24 17. 1 12 243 19. 3 EXERCISES 16.5 N 2 2.5 .5 21. (c) PAGE 1097 (b) y共e z e x 兲 5. (a) 0 (b) 2兾sx 2 y 2 z 2 7. (a) 具e y cos z, e z cos x, e x cos y典 2.5 16 35 3 1. (a) 0 (b) 3 3. (a) ze x i 共xye z yze x 兲 j xe z k 2.5 11. 3 23. 共4a兾3 , 4a兾3兲 if the region is the portion of the disk x 2 y 2 苷 a 2 in the first quadrant 27. 0 PAGE 1072 2 3 PAGE 1082 x 0 EXERCISES 16.2 N 1. 40 3. f 共x, y兲 苷 x 2 3xy 2y 2 8y K 7. f 共x, y兲 苷 ye x x sin y K 5. Not conservative 2 3 9. f 共x, y兲 苷 x ln y x y K 1 13. (a) f 共x, y兲 苷 2 x 2 y 2 (b) 2 11. (b) 16 2 15. (a) f 共x, y, z兲 苷 xyz z (b) 77 17. (a) f 共x, y, z兲 苷 ye xz (b) 4 19. 4兾e 21. It doesn’t matter which curve is chosen. 23. 30 25. No 27. Conservative 31. (a) Yes (b) Yes (c) Yes 33. (a) No (b) Yes (c) Yes 4 29. III 35. (a) 1. 4 3 (b) e x sin y e y sin z e z sin x 9. (a) Negative (b) curl F 苷 0 11. (a) Zero (b) curl F points in the negative z-direction 13. f 共x, y, z兲 苷 xy 2z 3 K 15. Not conservative 17. f 共x, y, z兲 苷 xe yz K 19. No Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 9 2 97909_Ans_Ans_pA126-134.qk_97909_Ans_Ans_pA126-134 10/14/10 5:11 PM Page 130 A130 APPENDIX I EXERCISES 16.6 N ANSWERS TO ODD-NUMBERED EXERCISES PAGE 1108 1. P: no; Q: yes 3. Plane through 共0, 3, 1兲 containing vectors 具 1, 0, 4典 , 具 1, 1, 5典 5. Hyperbolic paraboloid 7. 2 1 s3 x yz苷 2 2 3 37. x 2z 苷 1 39. 3 s14 41. s14 4 43. 15 共3 5兾2 2 7兾2 1兲 45. 共2兾3兲(2 s2 1) 3x y 3z 苷 3 33. 47. 2 s21 1 35. [ln(2 s21 ) ln s17 ] 17 4 49. 4 51. A共S兲 s3 R 2 53. 13.9783 55. (a) 24.2055 (b) 24.2476 √ constant 57. z 0 45 8 [ ] 15 s14 16 ln (11s5 3s70 )兾(3s5 s70 ) 59. (b) 0 2 _2 x 0 u constant y 1 1 9. z 0 2 u constant 2 y 1 0 2 1 1 0x (c) x02 x0 s36 sin 4u cos 2v 9 sin 4u sin 2v 4 cos 2u sin 2u du dv √ constant 61. 4 z 0 63. 2a 2共 2兲 EXERCISES 16.7 1. 49.09 _1 _1 _1 y 0 0 1 1 PAGE 1120 3. 900 9. 171 s14 x N 5. 11s14 15. 共兾60兲(391s17 1) 713 1 2 3 (2s2 1) 13. 364 s2 兾3 11. s21兾3 17. 16 23. 180 25. 3 27. 0 33. 4.5822 35. 3.4895 11. 7. 4 19. 12 21. 4 31. 2 29. 48 8 3 xxS F ⴢ dS 苷 xxD 关P共 h兾 x兲 Q R共 h兾 z兲兴 dA, where D 苷 projection of S on xz-plane 39. 共0, 0, a兾2兲 41. (a) Iz 苷 xxS 共x 2 y 2 兲 共x, y, z兲 dS (b) 4329 s2 兾5 8 43. 0 kg兾s 45. 3 a 3 0 47. 1248 37. z 0 √ constant _1 _1 y _1 0 0 1 1 x EXERCISES 16.8 u constant IV 15. II 17. III x 苷 u, y 苷 v u, z 苷 v y 苷 y, z 苷 z, x 苷 s1 y 2 14 z 2 x 苷 2 sin cos , y 苷 2 sin sin , z 苷 2 cos , 0 兾4, 0 2 or x 苷 x, y 苷 y, z 苷 s4 x 2 y 2, x 2 y 2 2 25. x 苷 x, y 苷 4 cos , z 苷 4 sin , 0 x 5, 0 2 13. 19. 21. 23. [ 3. 0 5. 0 11. (a) 81兾2 z 苷 ex sin , 0 x 3, 0 2 PAGE 1127 9. 80 7. 1 (b) 5 z 0 5 ] 29. x 苷 x, y 苷 ex cos , N 2 0 (c) x 苷 3 cos t, y 苷 3 sin t, z 苷 1 3共cos t sin t兲, 0 t 2 1 z 0 2 2 y 0 2 x 4 z 2 0 _2 1 1 y 31. (a) Direction reverses 0 1 0 x 2 (b) Number of coils doubles _2 y 0 2 2 0 _2 x 17. 3 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA126-134.qk_97909_Ans_Ans_pA126-134 10/14/10 5:11 PM Page 131 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I EXERCISES 16.9 5. y 苷 e 2x 共c1 cos x c2 sin x兲 PAGE 1133 N 5. 7. 9兾2 9. 0 11. 32兾3 13. 2 81 15. 341 s2兾60 20 arcsin(s3兾3) 17. 13兾20 19. Negative at P1 , positive at P2 9 2 7. y 苷 cos x 3 2 CHAPTER 16 REVIEW N x 11. 3 _3 8 yp Exercises 1. (a) Negative 7. 110 3 11 12 9. 17. 8 5. False 11. True (b) Positive 4兾e 1 6 25. 29. 64兾3 5. 19. y 苷 c1 cos ( 2 x) c 2 sin ( 2 x) 3 cos x 1 13. 0 27. 共兾60兲(391 s17 1) 37. 4 1 13. yp 苷 共Ax B兲e x cos x 共Cx D兲e x sin x 15. yp 苷 Axe x B cos x C sin x 17. yp 苷 xex 关共Ax 2 Bx C 兲 cos 3x 共Dx 2 Ex F兲 sin 3x兴 4 15 11. f 共x, y兲 苷 e y xe xy 33. 2 The solutions are all asymptotic to yp 苷 101 cos x 103 sin x as x l . Except for yp , all solutions approach either or as x l . _3 3. 6 s10 (27 5 s5 ) e 1 PAGE 1136 True-False Quiz 1. False 3. True 7. False 9. True 1 x 10 3 sin x e x 6x 1 2 9. y 苷 e x ( 2 x 2 x 2) 0 in quadrants I, II; div F 0 in quadrants III, IV 21. div F 11 2 A131 39. 21 1 1 21. y 苷 c1e c2 xe e 23. y 苷 c1 sin x c 2 cos x sin x ln共sec x tan x兲 1 25. y 苷 关c1 ln共1 ex 兲兴e x 关c2 ex ln共1 ex 兲兴e 2x x x 2x [ ] 27. y 苷 e x c1 c 2 x 2 ln共1 x 2 兲 x tan1 x 1 CHAPTER 17 EXERCISES 17.1 N EXERCISES 17.3 PAGE 1148 1. y 苷 c1 e 3x c 2 e2x 3. y 苷 c1 cos 4x c 2 sin 4x 5. y 苷 c1 e 2x兾3 c 2 xe 2x兾3 7. y 苷 c1 c 2 e x兾2 2x 9. y 苷 e 共c1 cos 3x c 2 sin 3x兲 11. y 苷 c1 e (s31) t兾2 c 2 e (s31) t兾2 [ 1 0.02 1.4 I共t兲 苷 e sin 20t 3 3 15. Q共t兲 苷 e10t [ 250 cos 20t 500 sin 20t] 3 3 250 cos 10t 125 sin 10t 17. y 苷 3e e 4x 19. y 苷 e 2x兾3 3 xe 2x兾3 3x 21. y 苷 e 共2 cos x 3 sin x兲 3 125 , 2 4x4 2x e 1 7 33x 2xe 2x 25. y 苷 5 cos 2x 3 sin 2x 29. y 苷 e2 ex e1 e1 31. No solution 33. (b) 苷 n 2 2兾L2, n a positive integer; y 苷 C sin共n x兾L兲 35. (a) b a 苷 n, n any integer (b) b a 苷 n and c cos a 苷 e ab unless cos b 苷 0, then d cos b c sin a 苷 e ab d sin b (c) b a 苷 n and c cos a 苷 e ab unless cos b 苷 0, then d cos b c sin a 苷 e ab d sin b EXERCISES 17.2 1. y 苷 c1e 49 12 c=20 c=25 c=30 3 10t 5 _10 3x 5. c=15 13. Q共t兲 苷 共e10t兾250兲共6 cos 20t 3 sin 20t兲 2x 27. y 苷 2e 6 _0.11 3 23. y 苷 e 1 0 ] f 1 7 3. x 苷 5 e6t 5 et 0 or as x l . g _3 PAGE 1163 1. x 苷 0.35 cos (2 s5 t) 7. c=10 13. P 苷 et c1 cos (10 t) c 2 sin (10 t) 15. All solutions approach either 10 1 N EXERCISES 17.4 N PAGE 1168 xn x 3n 3 1. c0 兺 苷 c0 e x 3. c0 兺 n 苷 c0 e x 兾3 n! 3 n! n苷0 n苷0 共1兲n 2n 共2兲n n! 2n1 x c1 兺 x 5. c0 兺 n n苷0 2 n! n苷0 共2n 1兲! n x 苷 c0 c1 ln共1 x兲 for x 1 7. c0 c1 兺 n苷1 n x 2n 2 9. 兺 n 苷 e x 兾2 n苷0 2 n! 共1兲n225 2 ⴢ ⴢ 共3n 1兲2 3n1 x 11. x 兺 共3n 1兲! n苷1 ⱍ ⱍ CHAPTER 17 REVIEW N PAGE 1169 True-False Quiz 1. True 3. True N PAGE 1155 c2 e x 657 cos 2x 654 sin 2x 3. y 苷 c1 cos 3x c2 sin 3x 1 2x 13 e Exercises 1. y 苷 c1e x兾2 c2 e x兾2 3. y 苷 c1 cos(s3 x) c2 sin(s3 x) Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. kg 97909_Ans_Ans_pA126-134.qk_97909_Ans_Ans_pA126-134 10/14/10 5:11 PM Page 132 A132 APPENDIX I ANSWERS TO ODD-NUMBERED EXERCISES 21. y 苷 6x 15 23. 2x 3y 19 苷 0 25. 5x y 苷 11 27. y 苷 3x 2 29. y 苷 3x 3 31. y 苷 5 33. x 2y 11 苷 0 35. 5x 2y 1 苷 0 5. y 苷 e 2x共c1 cos x c2 sin x 1兲 1 1 7. y 苷 c1e x c2 xe x 2 cos x 2 共x 1兲 sin x 1 1 3x 2x 2x 6 5 xe 9. y 苷 c1e c2 e 11. y 苷 5 2e6共x1兲 13. y 苷 共e 4x e x 兲兾3 15. No solution 37. m 苷 3 , 39. m 苷 0, 1 b苷0 共2兲nn! 2n1 17. 兺 x n苷0 共2n 1兲! 19. Q共t兲 苷 0.02e10t共cos 10t sin 10t兲 0.03 21. (c) 2兾k ⬇ 85 min (d) ⬇17,600 mi兾h 41. m 苷 4 , 3 b 苷 2 y b 苷 3 y y 0 0 x 0 x y=_2 x _2 _3 APPENDIXES EXERCISES A 3. 1. 18 ⱍ ⱍ 9. x 1 苷 43. PAGE A9 N 5. 5 s5 再 x1 x 1 11. x 2 1 0 _1 17. 共3, 兲 x 0 0 19. 共2, 6兲 47. 2 3 49. y y 6 y4 23. [1, 2 ) 21. 共0, 1兴 1 0 1 _1 1 _2 1 2 0 0 _1 _œ„ 3 33. 共, 1兴 51. y y=1+x 0 œ„ 3 共0, 1兲 35. 共1, 0兲 傼 共1, 兲 _1 1 0 x 0 1 y=1-2x ( 14 , ) 0 1 4 39. 10 C 35 41. (a) T 苷 20 10h, 0 h 12 3 4 (b) 30C T 20C 43. 2 45. 2, 3 47. 共3, 3兲 49. 共3, 5兲 51. 共, 7兴 傼 关3, 兲 53. 关1.3, 1.7兴 55. 关4, 1兴 傼 关1, 4兴 共c b兲兾a 57. x 共a b兲c兾共ab兲 59. x (b) 共3.5, 3兲 53. 共0, 4兲 55. (a) 共4, 9兲 59. y 苷 x 3 61. (b) 4x 3y 24 苷 0 EXERCISES C N PAGE A15 5. 2 s37 3. s74 y 7. 2 19. 9 7. ( 2 , 0), 2 1 1 3. x 2 y 2 苷 65 9. ( 14 , 14 ), s10兾4 13. Ellipse y y y 0 0 2 x xy=0 x 57. 共1, 2兲 PAGE A23 1. 共x 3兲 共 y 1兲2 苷 25 11. Parabola 9. 2 x=3 3 N 2 5. 共2, 5兲, 4 EXERCISES B x 1 2 31. (s3, s3 ) 29. 共, 兲 37. 共, 0兲 傼 x2 x 1 2 0 2 27. [1, 2 ] 25. 共, 1兲 傼 共2, 兲 0 x 0 15. 关1, 兲 _2 1. 5 17. y 7. 2 x for x 1 for x 1 13. 共2, 兲 45. y x _4 0 4 x _2 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA126-134.qk_97909_Ans_Ans_pA126-134 10/14/10 5:11 PM Page 133 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I 15. Hyperbola y _5 17. Ellipse y 4 y= 5 x 1 5 0 EXERCISES D x 0 1 _2 4 PAGE A32 N 1. 7兾6 3. 兾20 5. 5 11. 67.5 13. 3 cm 15. 2 3 17. 19. y 7. 720° 9. 75° rad 苷 共120兾兲 y x 1 2 0 _1 y=_ 5 x 0 x x 315° 19. Parabola 21. Hyperbola y x y=_ 3 x y x y= 3 1 0 _1 _1 3π _ 4 21. y 1 A133 2 rad 0 x 0 x _1 23. Hyperbola 23. sin共3兾4兲 苷 1兾s2, cos共3兾4兲 苷 1兾s2, tan共3兾4兲 苷 1, csc共3兾4兲 苷 s2, sec共3兾4兲 苷 s2, cot共3兾4兲 苷 1 25. sin共9兾2兲 苷 1, cos共9兾2兲 苷 0, csc共9兾2兲 苷 1, cot共9兾2兲 苷 0, tan共9兾2兲 and sec共9兾2兲 undefined 25. Ellipse y y 27. sin共5兾6兲 苷 2 , cos共5兾6兲 苷 s3兾2, tan共5兾6兲 苷 1兾s3, 1 csc共5兾6兲 苷 2, sec共5兾6兲 苷 2兾s3, cot共5兾6兲 苷 s3 (1, 2) 0 29. cos 苷 5 , tan 苷 4 , csc 苷 3 , sec 苷 4 , cot 苷 4 x x 29. Parabola y y 0 (3, 4) 1 15 (3 8 s2 ) 4 x 4 3 24 25 71. 0, , 2 65. 兾3, 5兾3 69. 兾6, 兾2, 5兾6, 3兾2 73. 0 x 兾6 and 5兾6 x 2 75. 0 x 兾4, 3兾4 x 5兾4, 7兾4 x 2 2 77. x y 1 1 2 33. y 63. 67. 兾4, 3兾4, 5兾4, 7兾4 2 31. Ellipse 5 苷 s5兾3, cos 苷 23 , tan 苷 s5兾2, csc 苷 3兾s5, cot 苷 2兾s5 1 33. sin 苷 1兾s10, cos 苷 3兾s10, tan 苷 3 , csc 苷 s10, sec 苷 s10兾3 1 35. 5.73576 cm 37. 24.62147 cm 59. 15 (4 6 s2 ) 61. 0 5 31. sin 0 27. Parabola 3 0 π 3 y x 5π 6 (3, 9) 79. 0 1 3 y x 5 0 x 0 35. y 苷 x 2 2x 37. 3π 2π 2 π x 5π 3π 2 39. y y 81. y 1 0 π 2 1 1 x 0 1 1 x _π 0 π 2π x 89. 14.34457 cm 2 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 97909_Ans_Ans_pA126-134.qk_97909_Ans_Ans_pA126-134 10/14/10 5:11 PM Page 134 A134 ANSWERS TO ODD-NUMBERED EXERCISES APPENDIX I EXERCISES E N PAGE A38 1. s1 s2 s3 s4 s5 3. 3 4 3 5 3 6 1 3 5 7 10 5. 1 3 5 7 9 7. 1 210 310 n10 10 9. 1 1 1 1 共1兲n1 11. 兺i 兺 13. i苷1 n i i1 21. 80 15. 5 兺 2i 17. i苷1 23. 3276 25. 0 31. n共n 2 6n 17兲兾3 27. 61 43. 45. 14 EXERCISES G N 19. 兺x i 49. 2 n1 25. 3 s2 关cos共3兾4兲 i sin共3兾4兲兴 [ 27. 5{cos tan ( )] i sin[tan1( 43)]} 1 4 3 关cos共兾6兲 i sin共兾6兲兴 31. 4 s2 关cos共7兾12兲 i sin共7兾12兲兴, i苷1 29. n共n 1兲 33. n共n 2 6n 11兲兾3 35. n共n 3 2n 2 n 10兲兾4 41. (a) n 4 (b) 5 100 1 (c) 1 3 兺2 i苷0 23. (s7兾2)i 1 2 1 2 n i 21. 1 2i 3 29. 4关cos共兾2兲 i sin共兾2兲兴, cos共兾6兲 i sin共兾6兲, i苷1 19 19. 2 i 17. 4i, 4 (2 s2 )关cos共13兾12兲 i sin共13兾12兲兴, 14 关cos共兾6兲 i sin共兾6兲兴 35. 512 s3 512i 33. 1024 37. 1, i, (1兾s2 )共1 i 兲 (d) an a0 n n2 97 300 39. (s3兾2) 2 i, i Im i 2 Im 0 PAGE A54 1 Re 1. 8 4i 9. 1 2 i 1 2 0 Re _i 1. (b) 0.405 EXERCISES H 1 N 3. 13 18i 11. i 13. 5i 41. i 43. 2 (s3兾2) i 45. e 2 3 47. cos 3 苷 cos 3 cos sin2, 1 PAGE A64 5. 12 7i 7. 11 13 15. 12 5i, 13 10 13 i sin 3 苷 3 cos2 sin sin3 Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.