Algebra 2 CP Chapter 7 Test Review Name _____________________ Graph the following functions and determine the domain and range of the function. Also, determine whether each function represents exponential growth or decay. Then, describe the shifts from the parent function y = a∙bx. x 1 1. y 2 3 Growth / Decay 1 x 5 2 Growth / Decay D = ______ R = ______ D = ______ Shifts:__________________ Shifts:__________________ 4. y 3 Growth / Decay 1 5. y 3 1 3 Growth / Decay D = ______ R = ______ D = ______ x3 2. 3. y 3e x y Growth / Decay R = ______ D = ______ R = ______ Shifts:__________________ x2 1 Shifts:__________________ 6. y 3e x 2 2 Growth / Decay R = ______ Shifts:__________________ D = ______ R = ______ Shifts:__________________ 7-9 Use the following information. You deposit $2200 in an account that earns 3% annual interest. Find the balance after 15 years if the interest is compounded with the given frequency. Round answers to the nearest cent. 7. monthly 8. quarterly 9. continuously 10. The population of a city can be modeled by P 125,000e0.02t where t is the number of years since 1990. What was the population in 1995? 11. You bought a motorcycle for $5800. It depreciates at a rate of 7.5% annually. If the motorcycle is now worth $1200, how long ago did you buy it? 12-13 Use the following information. You bought a CD for $15000. Four years later it was worth $22,525. Calculate the rate of interest compounded with the given frequency. 12. Semi-annually 13. Continuously 14. You invest $1500 in a stock whose value has been increasing by approximately 5% per year. The time required for an initial investment I0 to grow to I can be modeled where I0 and I are measured I ln I0 in dollars and t is measured in years by the following equation: t 0.049 a. How long before your investment doubles? b. How long before your investment triples? Rewrite the equation in exponential form. 15. log 10 1 18. log 25 125 16. log 4 3 2 19. 1 1 4 17. log 1 3 9 ln 0.135 2 1 2 20. ln 20.086 3 Write each equation in logarithmic form. 23. 16 2 81 3 26. e 3 1.948 5 125 22. 3 24. e 4 54.598 25. e 3 0.050 3 4 1 27 21. 3 2 Evaluate without a calculator. 27. 28. log 1 128 log 4 64 29. log 7 2 30. 33. 7 6x 25 7 2 x 5 2 x 20 1 125 y ln x 3 1 8 31. 2 34. ln e 3 x 32. 9 2 p 1 27 p 4 35. e x7 Find the inverse of the function. y log 15 x 36. 37. 39. 2 x 1 1 343 40. ln 42 y 2 log 3 x 2 38. y log 4 x 3 y ln x 1 1 41. y 3 ln x 2 Graph the function and state its domain and range. Also, describe the horizontal and vertical shifts from the parent function. 42. f x log 3 x 2 43. f x log 2 x 4 44. f x ln x 1 D = _______ R = _______ D = _______ R = _______ Shifts:__________________ Shifts:__________________ D = _______ R = _______ Shifts:_______________ Expand the expression by rewriting. 45. log 4 5x 48. log 6 5x3 6 46. log 8 x 2 49. ln 4 x2 Condense the expression by writing as a single logarithm. log 3 4 log 3 y 3 log 3 x 2 log x log x 4 51. 52. x 4 47. log 3 50. ln 53. 2 ln x 4 ln 3 ln y 3x3 5 Use the Change-of-Base formula to evaluate. Round to the nearest thousandth. log 7 12 log 5 1.25 54. 55. 56. log 4 112 Use the approximate logarithms to evaluate the logarithm. log 4 0.602 log 7 0.845 log 3 0.477 57. log 5 4 58. log 45 log 5 0.699 59. log 105 Use log 12 3 0.442 and log 12 7 0.783 to approximate the value of each expression. 60. log 12 21 61. log 12 63 62. log 12 7 3 Solve. 1 63 9 x 3 3x 64. 36 8 x 1 6 4 x 1 65. 4 x 2 16 x 4 66. 8 p 50 67. 8 y 4 15 68. 7.6 d 3 57.2 69. log 6 2 x 6 log 6 x 2 70. log 7 2 x log 7 5 x 71. log 3 x 2 log 3 3x 72. log 6 3 y 5 log 6 2 y 3 73. log 9 3u 14 log 9 5 log 9 2u 74. 4 log 2 x log 2 5 log 2 405 77. log b 3 1 2 80. log 16 9 x 5 log 16 x 2 1 83. 2e 3 x 5 2 86. ln 5x ln 3x 9 1 2 log 2 4 x 4 5 76. log 2 x 3 78. log 6 4 x 12 2 79. log 10 4 log 10 w 2 81. e x 2 4 21 82. e 8 x 50 84. ln x 3 5 2 85. ln 5 x 3 3.6 75. Write an exponential function y ab x whose graph passes through the given points. 87. (1, 4) and (2, 16) 88. (2, 2) and (3, 1) Use the table of values to create an exponential model that best fits the data. 89. x 1 2 3 4 5 6 y 3.36 x y 1 5.4 9.41 26.34 73.76 206.52 548.27 90. 2 9.72 3 4 5 6 17.496 31.493 56.687 102.04 Answer Key 1. Decay D = (, ) R = (0, ) None 4. Growth 7. $3448.35 D = (, ) R = (1, ) Left 3, Down 1 8. $3444.50 2. Growth 5. Decay D = (, ) R = (0, ) None D = (, ) R = (1, ) Right 2, Up 1 9. $3450.29 3. Growth D = (, ) R = (0, ) None 6. D = (, ) R = (2, ) Left 2, Down 2 Growth 10. 138, 146 people 11. 20.2 yrs 12. 10.4% 16. 4 1 13. 10.2% 1 17. 9 1 4 21. log 5 125 3 26. ln 1.948 31. x = 2 3 1 5 36. y 15 41. y e 1 2 14a. 14.1 years 3 3 1 3 27 2 19. e 0.135 18. 25 2 125 16 4 81 3 3 20. e 20.086 23. log 2 24. ln 54.598 4 27. 3 28. -7 29. -3 30. x = -5 32. p = 14 33. x = 34. 3 35. 42 22. log 3 x 2 37. y 3 2 x 1 15. 10 10 14b. 22.4 yrs 11 7 38. y 4 3 x 39. y e x 3 25. ln 0.050 3 40. y e x 1 1 x2 3 42. D = (2, ) R = (, ) Right 2 43. D = (0, ) R = (, ) Down 4 44. D = (0, ) R = (, ) Down 1 45. log 4 5 log 4 x 46. 2 log 8 x 47. log 3 x log 3 4 48. log 6 5 3 log 6 x 1 49. ln 4 2 ln x 50. ln 3 3 ln x ln 5 51. log 3 4 x 3 y 52. log 54. 1.277 55. 3.404 56. 0.139 57. 0.097 58. 1.653 59. 2.021 60. 1.225 61. 1.667 62. 0.341 63. x = -2 64. x = ¼ 65. x = 10 66. p = 1.881 67. y = -2.698 68. d = -1.005 69. x = 6 70. x = 72. y = 8 73. u = 2 74. x = 3 75. x = 9 76. x = 8 77. b = 9 78. x = 6 79. w = 25 80. x = 3 81. x ≈ 4.833 82. x ≈ -0.489 83. No Solution 84. x ≈ 17.086 85. x ≈ 6.720 86. x ≈ 23.242 87. y 4 53. ln x2 y 81 1 88. y 8 2 x 89. y 1.2 2.8 x 1 3 x2 x4 71. x = 1 90. y 3 1.8 x x