NORTH COBB HIGH SCHOOL AB CALCULUS AP PREREQUISITE PACKET The AP Course: AP Calculus AB is a college level course covering material traditionally taught in the first semester of college calculus. The course is taught in one semester. BC Calculus, corresponding to Calculus II at most universities, is taught during the second semester. Students are encouraged to take both semesters of AP Calculus. The Prerequisite Packet: Students need a strong foundation to be ready for the rigorous work required throughout the class. Completing the prerequisite packet should prepare you for the material to be taught in the course. This packet consists of material studied during primarily AC Math 3 but also some topics covered in AC Math 1 and Math 2. Students should anticipate working approximately 10 hours to complete it properly. This packet includes • A "Toolkit of Functions" - you should be familiar with each of the graphs • A formula and identities section. These are for your reference and do not need to be memorized at this time. • A unit circle template with which to practice your unit circle • A list of skills that you will need for AP Calculus. If you feel you are weak in any of the areas, let us know and we will be glad to help you. • Calculus Prerequisite Problems. Please show all work. Answers are provided at the end of the packet. Calculators: Students will be using a graphing calculator throughout the course. A graphing calculator is required on the AP test. We will be using a TI-84 in class, but a TI­ NSpire or TI-89 calculator are also good choices. Toolkit of Functions Students should know the basic shape of these functions and be able to graph their transformations without the assistance of a calculator. Constant Cubic f(x) = a f(x) Identity f(x) = x Absolute Value f(x) =I x I Reciprocal 1 f(x) = ­ x Quadratic f(x) =x 2 =x 3 Square Root f(x) = JX Greatest Integer f(x) =[ x ] Exponential f(x) = a" Logarithmic f(x) = Inx Trig Functions f(x) = sinx f(x) = f(x) cosx = tanx Polynomial Functions: A function P is called a polynomial if P(x) == anxn + an_1x n-1+ Where n is a nonnegative integer and the numbers 00, 01, az, Even degree + a2x 2 + ~x + ao an are constants. Odd degree Leading coefficient sign Leading coefficient sign Positive Positive Negative Negative • Number of roots equals the degree of the polynomial. • Number of x intercepts is less than or equal to the degree. • Number of "bends" is less than or equal to (degree - 1). Formulas and Identities Trig Formulas: Arc Length of a circle: d L = r 8 or L = - . Zrtr 360 d 1 Area of a sector of a circle: Area = - r 2 e or Area = - . nr 2 360 2 Solving parts of a triangle: a sinA Law of Sines: b c sinC --=--=-­ sinB a 2 = b 2 +c 2 -2bc cosA b 2 =a 2 +c 2 -2ac cosB c 2 = a 2 + b 2 -2ab cosC Law of Cosines: Area of a Triangle: Area = ..!.. be sinA or 2 Area = ..!.. ac sinB 2 or Area = ..!.. ab sine 2 Hero's formula: Area = ~s(s - a)(s- b)(s - c) ,where s = semi perimeter Ambiguous Case: 8 is acute Compute: alt = adj. sin 8 opp < alt opp = alt opp>adj No triangle 1 triangle (right) 1 triangle 8 is obtuse or right opp :-:; adj No triangle opp > adj 1 triangle alt<opp<adj 2 triangles Does a triangle exist? Yes - when (difference of 2 sides) < (third side) < (Sum of 2 sides) Formulas and Identities. continued Trig Identities: Reciprocal Identities: 1 cscA= - ­ sinA 1 1 cotA= - ­ tan A secA=-­ cosA cosA cotA=-­ sin A sinA tan A = - ­ cosA Quotient Identities: Pythagorean Identities: sin-A + cos-A = 1 1 + cot-A = esc-A tan-A + 1 = sec-A Sum and Difference Identities: sin(A + B) = sinA cosB+cosA sinB sin(A - B) = sinA cosB - cosA sinB cos(A + B) = cosA cosB - sinA sinB cos(A - B) = cosA cosB + sinA sinB tan (A + B) = tan A + tanB I-tanAtanB tan (A - B) ­ ----- - tan A - tanB 1+ tanA tan B Double Angle Identities: sin(2A) = 2sinA cosA 2 tan A tan(2A) = --.,.----­ I-tan 2 A cos(2A) = cos-A - sin-A cos(2A) = 2cos 2A -1 cos(2A) = 1 - Zsin-A Half Angle Identities: . A 2 sm-=± JI-COSA 2 cos A = ±Jl+cosA 2 2 A l-cosA tan-=± 1 - - ­ 2 1 + cosA Polar Formulas: x = rcos8 tan -1 Y = 8 + 1t y = rsin8 x Geometric Formulas: Area of a triangle: A = J:.. bh Area of a trapezoid: A = J:.. h (b l + b2 ) 2 Area of an equilateral triangle: A = Area if a circle: A = nr' 2 J3 S2 4 Circumference of a circle: C = 2rcr or C = dn X <0 Unit Circle - Degrees and Radians D o o Place degree measures in the circles. tan O = - - - - - - Place radian measure in the squares. cot G= Place (cos O sin G) in parenthesis outside the square. cscf = _ Place tan e outside the parenthesis. secO> _ I _ SKILLS NEEDED FOR CALCULUS I. Algebra: *A. Exponents (operations with integer, fractional, and negative exponents) *B. Factoring (GCF, trinomials, difference of squares and cubes, sum of cubes, grouping) C Rationalizing (numerator and denominator) *D. Simplifying rational expressions *E. Solving algebraic equations and inequalities (linear, quadratic, higher order using synthetic division, rational, radical, and absolute value equations) F. Simultaneous equations II. Graphing and Functions *A. Lines (intercepts, slopes, write equations using point-slope and slope intercept, parallel, perpendicular, distance and midpoint formulas) B. Conic Sections (circle, parabola, ellipse, and hyperbola) *C Functions (definition, notation, domain, range, inverse, composition) *D. Basic shapes and transformations of the following functions (absolute value, rational, root, higher order curves, log, In, exponential, trigonometric. piece-wise, inverse functions) E. Tests for symmetry: odd, even III. Geometry A. Pythagorean Theorem B. Area Formulas (Circle, polygons, surface area of solids) C Volume formulas D. Similar Triangles * IV. Logarithmic and Exponential Functions *A. Simplify Expressions (Use laws of logarithms and exponents) *B. Solve exponential and logarithmic equations (include In as well as log) *C Sketch graphs *D. Inverses * V. Trigonometry **A. Unit Circle (definition of functions, angles in radians and degrees) B. Use of Pythagorean Identities and formulas to simplify expressions and prove identities *C Solve equations *D. Inverse Trigonometric functions E. Right triangle trigonometry *F. Graphs VI. Limits A. Concept of a limit B. Find limits as x approaches a number and as x approaches 00 * A solid working foundation in these areas is very important. Calculus Prerequisite Problems Work the following problems on your own paper. Show all necessary work. I. Algebra A. Exponents: (8x 3yz)X (2X)3 1) 4x X (yz%f B. Factor Completely: Hint: Factor as difference ofsquares first, then as the sum and difference ofcubes second. 2) 9x2 + 3x - 3xy - y (use grouping) r· 5/ 5) 15.\-7:.' 6) X -1 -3x -2 + 2x -3 3/ . ''I.' -·2.\/:: - 24x' 2 Hint: Factor GCF x 1/2 first Hint: Factor out GCF x-3 first C. Rationalize denominator/numerator: 7) 3-x 1-,.Jx-2 8) jX+I + 1 X D. Simplify the rational expression: 9) (x + 1)3 (x - 2) + 3(x + 1 )2 (x + 1)4 E. Solve algebraic equations and inequalities 10. - 11. Use synthetic division to help factor thefollowing, stateallfactors and roots. 10) p(x) = x3 + 4x 2 + x - 6 12) Explain why 3 "2 11) p(x) = 6x3 - 17x 2 - 16x + 7 cannot be a root of f(x) = 4x5 + cx3 - dx + 5 , where c and d are integers. (hint: You can look at the possible rational roots.) 13) Explain why f(x) = x4 + 7x2 + x - 5 must have a root in the interval [0,1], (0 ~ x ~ 1) Check the graph and use signs of f(O) and f(l) to justify you're answer. Solve: You may use your graphing calculator to check solutions. 14) (x + 3)2> 4 17) x < 20) x 2 < 4 1 x 15) x+5 x-3 18) xL9 x+l 21) ~ I 2x + 1 I 16) 3x 3 -14x 2 0 ~ 0 1 4 <- - 5x ~ 0 (Factor first) 1 4 -+-- > 0 19) x-l x-6 F. Solve the system. Solve the system algebraically and then check the solution by graphing each function and using your calculator to find the points of intersection. 22) x - Y + 1 = 0 y-x 2 = -5 23) x 2 - 4x + 3 = Y - x 2 + 6x - 9 = Y II. Graphing and Functions: A. Linear graphs: Write the equation of the line described below. 24) Passes through the point (2, -1) and has slope 1 -3" . 25) Passes through the point (4, - 3) and is perpendicular to 3x + 2y = 4. 26) Passes through ( -1, - 2) and is parallel to y = 3 5" x -1. B. Conic Sections: Write the equation in standard [orm and identify the conic. 28) 4x 2 -16x + 3y 2 + 24y + 52 = 0 27) x = 4y 2 + 8y - 3 C. Functions: Find the domain and range of the following. Note: domain restrictions - denominator i= 0, argument of a log or In > 0, radicand of even index must be ~ 0 range restrictions- reasoning, if all else fails, use graphing calculator 3 29) y = - ­ x-2 32) Y =~2x - 3 30) Y = log(x - 3) 33) Y= Ix-5 I 34) domain only: F+1 y -- -2 ­ 1 x - 35) Given f(x) below, graph over the domain [-3, 3], what is the range? X f (x) == 1 { ifx~O if -1 ~ x < 0 x - 2 if x <-1 Find the composition/inverses as indicated below. Let f(x) = x2 + 3x - 2 36) g -1 (x) g(x) = 4x - 3 h(x) 38) w -l(x), for x ~ 4 37) h -l(x) w(x)=~ = lnx 39) f(g(x)) 40) h(g(f(l))) 41) Does y = 3x 2 - 9 have an inverse function? Explain your answer. Let f(x) = 2x, g(x) = -x, and h(x) = 4, find 42) (f 0 g)(x) 44) Let (f 0 go h)(x) 43) s (x) = ~ t(x) = x2, find the domain and range of (s 0 t )(x). and D. Basic Shapes of Curves: Sketch the graphs. You may use your graphing calculator to verify your graph, but you should be able to graph the following by knowledge of the shape of the curve, by plotting a few points, and by your knowledge of transformations. 45) Y =~ 49) Y x 50) Y = x 2 - 4 1 x-2 = -­ ../25 - x2 53) f(x) = 1 47) Y = ~ 46) Y = lnx 48) Y = Ix-2 I IT 52) Y = 3 sin 2 (x - 6" 51) Y = 2-x ) if x < 0 x2 -25 x-5 if x o ~ 0, x ~ 5 if x = 5 E. Even, Odd, Tests for Symmetry: Identify as odd, even, or neither and justify you're answer. To justify your answer you must show substitution using -x! It is not enough to simply check a number. Even: 54) f(x) f (x) x3 + 3x 57) f(x) = sin 2x = f (-x) Odd: f (-x) = - f (x) 55) lex) = x L 6x2 + 3 58) f(x) = x2 + x 56) f(x) 3 = x ~X x2 59) f(x) = x(x2 -1) 60) f(x) = ~ 2 x 61) What type of function (even or odd) results from the product of two even functions? odd functions? Test for symmetry. Show substitution with variables to justify you're answer. Symmetric to y axis: replace x with - x and relation remains the same. Symmetric to x axis: replace y with - y and relation remains the same. Origin symmetry: replace x with - x, Y with - yard the relation is equivalent. 62) Y = x 4+ 63) Y = sin(x) X 2 64) Y = cos (x) ~ 65) x = y2 + 1 66) Y = x2 + 1 IV LOGARITHMIC AND EXPONENTIAL FUNCTIONS A. Simplify Expressions: 3 1 ( 27 1) 68) 3log3 3 - -log3 81 + -log3 4 3 67) log, ( 11) 72) lne 69) log, 27 74) In e 2 73) In 1 B. Solve equations: 76) log x2 - log 100 = log 1 77) 3 x+l = 15 V TRIGONOMETRY A. Unit Circle: Know the unit circle - radian and degree measure. Be prepared for a quiz. 78) State the domain, range and fundamental period for each function? a) y=sinx b) y= cosx c) y = tan x B. Identities: Simplify: 79) (tan 2x)(csC2X) . 1 (cscx)(tan-x) (sinx) 80) 1· cos- x 81) sec-x - tan- x 82) Verify: (1 - sin2x)(1 + tan-x) = 1 C. Solve the Equations 83) cos-r = 84) 2 sin(2x) = -{3, cos x + 2, 85) cos-x + sinx + 1 = 0, O:c:; x :c:; 2;r os x s 2rr D. Inverse Trig Functions: Note: Sin 86) Arcsinl -1 x = Arcsin x 88) ArccOs( ~J 89) sin[ ArCCOs( ~ J; 90. State domain and range for: Arcsin(x), Arccos (x), Arctan (x) E. Right Triangle Trig: Find the value of x. (Note: Degree measure!) 91. 93. x 10 A 180 ft B 60 ft c 93) The roller coaster car shown in the diagram above takes 23.5 sec. to go up the 23 degree incline segment AH and only 2.8 seconds to go down the drop from H to e. The car covers horizontal distances of 180 feet on the incline and 60 feet on the drop. Decimals in answer may vary. a. How high is the roller coaster above point B? b. Find the distances AH and He. c. How fast (in ftl sec) does the car go up the incline? d. What is the approximate average speed of the car as it goes down the drop? e. Assume the car travels along He. Is your approximate answer too big or too small? ( Advanced Mathematics, Richard G. Brown, Houghton Mifflin,1994, pg 336) F. Graphs: Identify the amplitude, period, horizontal, and vertical shifts of these functions. 94) Y = - 2sin(2x) 95) Y = -Jrcos( ~x + Jr) G. Be able to do the following on your graphing calculator: Be familiar with the I CALCI commands; value, root, minimum, maximum, intersect. You may need to zoom in on areas of your graph to find the information. Answers should be accurate to 3 decimal places. Sketch graph. 96. - 99. Given the following function f(x) = 96. Find all roots. 2x 4 - llx 3 - x 2 + 30x. Note: Window x min: -10 x max: 10 scale 1 y min: -100 y max: 60 scale 0 97. Find all local maxima. 98. Find all local minima. A local maximum or local minimum is a point on the graph where there is a highest or lowest point within an interval such as the vertex ofa parabola. 99. Find the following values: f (-1), f (2), f (0), f (.125) 100. Graph the following two functions and find their points of intersection using the intersect command on your calculator. y = x3 + 5x2 - 7x + 2 and y = .2x2 + 10 Window: x min:-lO y min: -10 x max: 10 scale 1 y max: 50 scale 0 VI. Functions and Models 101. The graphs of f and g are given. (a) State the values of f(-4) and g(3). (b) For what values of x if f(x)=g(x)? (c) Estimate the solution of the equation (d) On what interval is f decreasing? (e) State the domain and range of f. (f) State the domain and range of g. y r-, ",V /' '/ / i gj - ~-~V f/ , -.- 2 ......... ; --- - 1/1""_ ....... '1 I i ! 2 -- , 0 I -. f(x) = -1. \ ! I . . . L 102. The number N (in thousands) of cell ular p hone subscribers in M alaysia is shown in the table. (Midyear estimates are given.) t 1991 1993 1995 1997 I N 132 304 873 2461 I (a) Use the data to sketch a rough graph of N as a function of t. (b) Use your graph to estimate the number of cell-phone subscribers in Malaysia at midyear in 1994 and 1996. 103. If f(x) = 3x 2 -x+2, find f(2), f(-2), f(a), f(-a), f(a+1), 2f(a), f(a 2), [f(a)] 2, and f(a+h). 104. Find the domain of each function. x 3x-l a) j(x)=-­ b) g(u)=..[;;+.J4-u 105. Find an expression for the bottom half of the parabola x+(y-1) 2 =0. 106. A rectangle has perimeter 20 m. Express the area of the rectangle as a function of the length of one of its sides. 107. Find an expression for the function whose graph is the given curve. -16 -e ..,; -4 -.::: 108. Biologists have noticed that the chirping rate of crickets of a certain species is related to temperature, and the relationship appears to be very nearly linear. A cricket produces 113 chirps per minute at 70° F and 173 chirps per minute at 80° F. (a) Find a linear equation that models the temperature T as a function of the number of chirps per minute N. (b) What is the slope of the graph? What does it represent? (c) If the crickets are chirping at 150 chirps per minute, estimate the temperature. 109. At the surface of the ocean, the water pressure is the same as the air pressure above the water, 15lb/in 2. Below the surface, the water pressure increases by 4.34Ib/in 2 for every 10 ft of descent. (a) Express the water pressure as a function of the depth below the ocean surface. (b) At what depth is the pressure 100 Ib/rn 2? 110. Classify each function as a power function, root function, polynomial (state its degree), rational function, algebraic function, or logarithmic function. 2+1 (a) f(x) (b) g(x)=Jl-x 2 =if; (d)r(x)=x x 3 +x 111. Match each equation with its graph. Explain your choices. (Don't use a computer or graphing calculator). 8 (a) y=x 2 (b) y=x 5 (c) y=x ·10 112. Suppose the graph of f is given. Write equations for the graphs that are obtained from the graph of f as follows. (b) Shift 3 units downward. (a) Shift 3 units upward. (d) Shift 3 units to the left. (c) Shift 3 units to the right. (f) Reflect about the y-axis, (e) Reflect about the x-axis. (h) Shrink vertically by a factor of 3. (g) Stretch vertically by a factor of 3. 113. The graph of y = f(x) is given. Match each equation with its graph and give reasons for your choices. (a) y = f(x-4) (b) Y = f(x)+3 (c) Y = 1/3 f(x) (d) Y = -f(x+4) (e) y = 2f(x+6) 114. The graph of f is given. Use it to graph the following functions. (a) y = f(2x) (b)=f( 1/2 x) (c) Y = f(-x) (d) Y = -f(-x) 3 ·2 7 ·1 8 -2 115. Graph the following, not by plotting points, but by starting with the graph of one of the standard functions and applying the appropriate transformations. y 1 . ( =3"sm 1[1 X-tO 116. Find f+g, f - g, fg, and f/ g and state their domains. l(x)=x 3+2x 2 , g(x)=3x 2 - 1 117. Find the functions log, I(x) = sin X, g(x) = go I, 1 01, and gog and their domains. l--r; 118. Express the function in the form log. F(x) = (x 2 + l)'" 119. Use a graphing calculator to determine which of the given viewing rectangles produces the most appropriate graph of the function I(x) = 10+ 25x-x 3 • (a) [-4,4} by [-4,4] (b) [-10,10] by [-10,10] (c) [-20,20] by [-100,100] (d) [-100, 100] by [-200,200] 120. Use the given graphs of f and g to evaluate each expression, or explain why it is undefined. (b) g(f(O)) (a) f(g(2)) (e) (g 0 g)( -2) (d) (go/)(6) (c) (1 0 g)(O) (I) (/ 0 / )(4) ·3 121 and 122, Determine an appropriate viewing rectangle for the given function and use it to draw each graph. 121. I(x) = 5 + 20x _x 2 122. l(x)=~81-x4 123. Graph the ellipse 4x 2 + 2y 2 = 1 by graphing the functions whose graphs are the upper and lower halves of the ellipse. 124. Find all solutions of the equation correct to three decimal places. x 3 -9x 2 -4 = 0 125. Graph the given functions on a common screen. How are these graphs related? y=2 x , y=e x , y=5", y=20 x 126. Starting with the graph of y = e", write the equation of the graph that results from (a) shifting 2 units downward (b) shifting 2 units to the right (c) reflecting about the x-axis (d) reflecting about the y-axis (e) reflecting about the x-axis and then about the y-axis 127. Find the exponential function f(x) = Ca x whose graph is given. 24 22 20 18 16 14 12 10 8 6 4 2 ·1 3 4 128. Under ideal conditions a certain bacteria population is known to double every three hours. Suppose that there are initially 100 bacteria. (a) What is the size of the population after 15 hours? (b) What is the size of the population after t hours. (c) Estimate the size of the population after 20 hours. (d) Graph the population function and estimate the time for the population to reach 50,000. 129. Determine whether this function is one-to-one. t@ ~.5 I ~.o I ~.6 I :.3 1-~-.8---1-~-.0--- 130. Determine whether this function is one-to-one. -J -4 131. Here is a verbal description of a function. Determine whether this function is one­ to-one. P(t) is the height of a football t seconds after kickoff. For #132-134, find a formula for the inverse of the function. 132. f(x)=~./lO-3x ) 133. I(x) = e' 134. Y = In(x+3) For #135-136, find the exact value of each expression (non-calculator). 135. (a) log, 64 1 log, 36 (b) 136. (a) log., 1.25 + log., 80 (b) logs 10+ logs 20 - 3log s 2 137. Express the given quantity as a single logarithm. 2ln4-ln2 138. The graph shown gives a salesman's distance from his home as a function of time on a certain day. Describe in words what the graph indicates about his travels on this day. Distance from home (miles) 8 A.M. to NOON 2 4 6 P.M. Time (hours) Answers: (Remember - you must show all of your work!) 1. 4x ll / 3y4/ 3z 5. x 1 / 2(3x - 4)(5x + 6) 4. 7(3x2 + 4)(2x L 1) 7.1+~ 6. x·3(x - 2)(x - 1) ~ 1 - - or 0 ~ 3 x ~ 1 1 24. y=--x-- 3 28. 3 (X_2)2 (y+4)2 + 3 . = 4 2 17 3 3 y=-x-- =1 ellipse 31. 0: all reals R: x ~ 2 35. R: - 5 s Y < - 3 or 0 34. x >-1 and x ::j:. 1 38. Y = x2 + 4 x ~ 0, 39. f(g(x)) 43. - 8 44. D: -2 5 32. 0: x '?. 3/ 2 < x ~ 2 R: 0<y 67. - 2 61. even, even 68. -1 76. x = 10, -10 69. 3/2 77. 36. /-1 (x) ys3 81. 1 82. yes 83. Jr 84. ~ 0 = X <2 70. -1/3 b) D: allreals, R:-1:::x.:s,1 ,2JI 19. x> 6 or 1 < x < 2 + 3 37. h -l(x) = eX 4 41. no, explain 42. -2x 40. In 5 62. symm y axis 63. origin log 15 log 3 - 1 x<3 33. 0: all reals R: y You must show work on these! 54. odd 55. even 56. odd 60. even ~ 30. D: x > 3 Riall reals R: Y '?. 0 = 16x2 -12x - 2 15. -5 27. x = 4(y + 1)2 - 7 parabola 5 R: Y 1= 0 ~ 12. not a possible rational 23. (2,-1),(3,0) 3 7 26. Y =-x-- 29. 0: x 1= 2 3 18. [-3, -1) U [3, (0) 22. (3,4), (-2, -1) 25. 1 ' 14. x> -lor x < -5 17. 0 < x < 1 or x < -1 5 x2 - x + 1 (x + 1)2 9. ~-1 positive 5 3 21. - 8' < x < - 8' 20. -2 < x < 2 1 7 13. f(O) = neg and f(l) 16. x 8 11. (x + 1)(2x - 7)(3x -1); -1, 2" 10. (x -l)(x + 2)(x + 3); 1, -2, -3 root 3. (2x -1)(4x 2 + 2x + 1)(2x + 1)(4x 2 - 2x +1) 2. (3x + 1)(3x - y) 71.45 57. odd 58. neither 64. yaxis 65. x axis 72. 1 73. 0 74. 2 66. yaxis 75.-1 78. a) 0: all reals, R: -1 ~ x :::1 , 2 JI R: allreals,rr c) D: x1=rr/2 Jr Jr 7Jr 4Jr 6'3'6' 3 85. 3Jr 2 79. 1 80. sin-x 86. n 2 59. odd 87. Jr4 88. Jr6 ~ 89. 2 Arccos (x) D:[-l,l]. R: [O,II] 90. Arcsin(x) D: [-1,1] Range: [_ Jr, Jr] 2 2 Arctan (x) D: allreals R: 91. 10 sin 50 0 7.66 92. hint: draw altitude, x IJ 14.619 [-~,;] 93. a. HB 0 76.405 ft. b. AH 0 195.5448 ft., HC 0 97.148 c. speed up approx. 8.32 ft./sec d. speed down approx 34.696 ft./ sec e. Too small, since the distance traveled is longer the distance per foot would be greater. (Note: find average speed for the entire trip! 11.129 ft /sec) 94. A: 2, P: II 95 A = 97. rel max. (1.07,20.1) 99. f( -1) = -18 Jr, Per. 4, V.s. = 0 , h. s. = -2 Y = -Jr cos [~ (x + 2)] 96. - 1.5, 0, 2,5 98. rel. min (- .89, - 18. 48), (3.94, - 88) 100. 3 points of intersection - one is (-5.77,16.66) 100. Do not use trace to find points. Use CALC commands. 101. (a) -2,4 (b) -2 and 2 (c) x= -3 and 4 (d) [0,4] (e) d: [-4,4] r:[-2,3] (f) d: [-4,3] r:[0.5,4] 102. (b) 540 In 1994 and 1450 In 1996 103. f(2)=12, f(-2) = 16, f(a) = 2al\2 -a +2, f(-a)=3aI\2+a+2, f(a+ 1)=3aI\2+5a+4, 2f(a)=6aI\2-2a+4, f(2a)=12aI\2-2a+2, f(aI\2)=3aI\4 -a1\2 +2, [f(a))A2=9aI\4 -6aI\3+13aI\2-4a+4, f(a+h)=3aI\2 +6ah+3hI\2 -a-h+2 104. (a) (-00,1/3) U (1/3,00) (b) [0,4] 105. f(x) = 1-h (domain: x:S; 0) X + 1 if -1 < x < 2 106. A(L) = 10L -L1\2 domain 5<L<10 107. f(x) = 3 { --x+6 if 2<x~4 2 108. (a) T=1/6 N + 307/6 (b) 1/6 means thatfor each increase of 6 cricket chirps per minute corresponds to an increase of 1 degree F. (c) 76 degrees F 109. (a) P=0.434d + 15 (b) approx. 196 feet 110. (a) root fct. (b) algebraic because it Is the root of a polynomial (c) polynomial of degree 9 (d) rational function 111. (a) matches with h (b) matches with f and (c) matches with g. 112. (a) y = f(x)+3 (b) Y= f(x) -3 (c) Y = f(x-3) (d) Y= f(x+3) (e) y = -f(x) (f) Y= f(-x) (g) Y= 3f(x) (h) Y= 1/3 f(x) 113. (a) graph 3 (b) graph 1 (c)graph 4 (d) graph 5 (e) graph 2 114. (a) shrink horizontally by a factor of 2 (b) stretch horizontally by a factor of 2 (c) reflect the graph of f about the y-axis (d) reflect the graph of f about the y-axis, then about the x-axis 115. 116. (f+g)(x) =xI\3+5x'\2-1 d: all real numbers (f-g)(x)= xI\3-xI\2+1 d: all reals (fg)(x)=3x A5+6xA4-x A3-2s A2 d: all reals (fjg)(x)=(x A3 +2x A2)j(3xA2 -1) d: x cannot Equal ± ~ 117. (fog)(x)=sin(1-E) d:[O,oo) (joj)(x)=sin(sinx) d:(-oo,oo) (goj)(x)=I-.}sinx (gog)(x)=I-JI-E d:[O,tr],[2tr,3tr]efc d:(-oo,oo) 118. g(x)=x A2+1and F(x)=x AI0 119. c 120.(a) 5 (b) 3 (c)O (d) not defined (e) 4 (f) -2 121. [-10,30] by [-50,150] 122. [-4,4] by [-1,4] 123. graph y = +sqr((1-4x A2)j2) and -sqr((1-4x A2)j2) 124. about 9.05 125. All of these graphs approach 0 as x approaches negative infinity, all of them pass Through the point (0,1) and all of them are increasing and approach infinity as x Approaches infinity. 126. (a) y = eAx -2 (b) Y= e A(x-2) (c) y = -eAx (d) y = eA(-x) (e) y = - eA(-x) 127. f(x) = e(2 Ax) 128. (a) 3200 (b) Y = 100(2A(tj3)) (c) 10,159 (d) 26.9 hrs. 129. No, does not pass horizontal line test. 130. No 131. A football will attain every height up to its maximum height twice: once on the way up, and again on the way down. 1 2 10 -rr:: 134. j-'(x)=e x - 3 Hence,notltol.132. j-I(X)=_-x + - d:[O,oo) 133. j-I(X)={tlnx 3 3 135 (a) 6 (b) -2 136. (a) 2 (b) 2 137. In8 138. The salesman travels away from home from 8 am To 9 am and is then stationary until 10:00. The salesman travels farther away from 10 until noon. There is no change in his distance from home until 1:00, at which time the distance from home decreases until 3:00. Then the distance starts increasing again, reaching the maximum distance away from home at 5:00. There is no chance from 5 until 6, and then the distance decreases rapidly until 7:00 pm, at which time the salesman reaches home.