Exponential and Logarithmic Functions: Math 30 – 1: Diploma Review: 1. (4π₯ −3 π¦ 5 )2 is equal to: A. B. C. D. 16π¦ 10 π₯6 4π¦ 10 π₯6 16π¦ 10 π₯3 16π₯ 6 π¦ 10 1 2. (36π₯ −4 )−2 is equal to: A. 6 π₯2 B. −18π₯ 2 C. D. π₯2 6 π₯ −4.5 6 3. When 16(8)π₯−1 is converted to base 2, the exponent is: A. B. C. D. 3π₯ + 1 3π₯ + 3 7π₯ − 7 12π₯ − 12 1 4. If 42π₯−7 = 64, then the value of √π₯ is: A. 2 B. √2 C. √5 D. 3 2 5. The solution to the equation 25π₯+1 = 53(π₯−1) , to the nearest tenth, is π₯ = ________. 1 π₯−3 6. The solution to the equation (8) = (2)(16)2π₯+1, to the nearest hundredth, is x = ______. 7. The solution to 82π₯−1 = 16, to the nearest tent, is x =_____. 8. Which equation represents an exponential function? A. π¦ = 2π₯ 8 B. π¦ = (−3)π₯ C. π¦ = 3π₯−2 2 1 D. π¦ = 3π₯ Use the following to answer the next three questions: A student is attempting to sketch the graph of the function π(π₯) = 3π₯−2 − 1 without using a graphing calculator. 9. Which of the following is an asymptote of the graph? A. B. C. D. π₯ = −2 π₯=2 π¦=1 π¦ = −1 10. The range of π is: A. B. C. D. π(π₯) ∈ π {π(π₯)|π(π₯) > −2, π(π₯) ∈ π } {π(π₯)|π(π₯) ≥ −1, π(π₯) ∈ π } {π(π₯)|π(π₯) > −1, π(π₯) ∈ π } 11. The x-intercept of the graph is: A. B. C. D. 0 2 3 There is no x-intercept 12. What is the y-intercept for the graph of y = bx - 2, b > 1? A . ο1 b2 B. -b2 C . 1 b2 D. 2 13.In the equation y = bx, b > 1, x is replaced by x - 3 and y is replaced by y - 4. Which of the following statements describes the transformation? A. The point (x, y) on the graph of y = bx has been transformed to the point (x + 3, y + 4). B. The point (x, y) on the graph of y = bx has been transformed to the point (x - 3, y - 4). C. The graph of y = bx has been translated 4 units to the right and 3 units up. D. The graph of y = bx has been translated 3 units to the left and 4 units down. 14. The graph of f(x) = ax, a > 1, is transformed into g(x) = 4ax + 3 - 2. Which characteristic remains the same? A. domain B. range C. x-intercept D. y-intercept 15. The graph of the function f(x) = 3ax + 2, a > 0, has the same horizontal asymptote as which of the following? A. y = -f(x) - 4 B. y = -f(x) - 2 C. y = -f(x) + 2 D. y = -f(x) + 4 16. Mary was asked to solve for x and y in the exponential equations 5x + 3y = 1 and 1 25x ο« y ο½ . Which of the following linear equations would lead to a correct solution? 5 A. x + 3y = 1, x + y = -1 B. x + 3y = 0, 2(x + y) = -1 C. x + 3y = 1, 2x + y = -1 D. x + 3y = 0, x + y = -2 17. Which function(s) would you graph to solve the equation 16 A. y1 = 16-0.5x, y2 = 0.54x + 3 B. y1 ο½ 16 C. y1 ο½ ο ο¨ο© 1 2 1 2x ο 4x ο« 3 ο¨ο© 1 2 4x ο« 3 1 ο« 16 2 D. y1 = 4x, y2 ο½ ο¨ο© 1 2 x 4x ο« 3 1 ο x 2 ο½ ο¨ο© 1 2 4x ο« 3 graphically? 18. Given the function f(x) = 2x, match the graph with the correction equation. Graph 1 Graph 2 Graph 3 Graph 4 Place the number of the graph that corresponds to y = -f(x) in the first box. Place the number of the graph that corresponds to y = f(-x) in the first box. Place the number of the graph that corresponds to y = f -1(x) in the first box. Place the number of the graph that corresponds to y = -f(-x) in the first box. 19. The function f(x) = -5(2x) is transformed by a translation 2 units right and 5 units down. The transformed function passes through the point (x, -10). Determine the value of x. 20. The graph of f (x) = logb x, b > 1, is translated such that the equation of the new graph is expressed as y - 2 = f (x - 1). The domain of the new function is A. {x | x > 0, x ο R} B. {x | x > 1, x ο R} C. {x | x > 2, x ο R} D. {x | x > 3, x ο R} 21. The x-intercept of the function f (x) = log5 x + 3 is: A. 5-3 B. 0 C. 1 D. 53 1 22. The equation y ο½ log 2 x can also be written as: 3 x y A. y ο½ 2 3 B. x ο½ 2 3 C. 23x = y D. 23y = x 23. The range of the inverse function, f -1, of f (x) = log4 x, is: A. { y | y > 0, y ο R} B. { y | y < 0, y ο R} C. { y | y ≥ 0, y ο R} D. { y | y ο R} 24. A graph of the function y = log3 x is transformed. The image of the point (3, 1) is (6, 3). The equation of the transformed function is: A. y = 3 log3 (x - 3) B. y = 3 log3 (x + 3) C. y - 3 = log3 (x - 3) D. y + 3 = log3 (x + 3) 25. If log27 x = y, then log3 x equals: A. 3y B. 2 C. 3y D. 2y 3 4y 26. If log 4 4096π₯ = 64, then π₯ equals: 32 A. B. C. D. 43 458 46 432 27. The graph of log π₯ π¦ = 1 is: 28. To the nearest tenth, the y-intercept of the graph of log 5 (π¦ + 2) = π₯ + 1 is _______. 2 29. If log π 81 = 3, then the value of π to the nearest whole number is _____________. 30. Which of the following has a negative value? A. − log 4 0.1 5 B. log 4 2 2 C. log 1 3 2 2 D. log 4 3 31. The value of the expression log √2 8 + 2log 9 3, to the nearest tenth, is ______. 32. Given the equation log 7 π₯ = log 4 60, the value of x to the nearest whole number is ____. 33. If log π₯ 27 = log 3 12, the value of x to the nearest whole number is Use the following to answer the next question: 1 Three students were asked to find an alternate expression for log π₯ , π₯ > 0. Alex gave the answer − log π₯ Bahman gave the answer log(−π₯) Connor gave the answer log(π₯ −1 ) 34. The correct alternative answer was given by: A. Connor only B. Alex and Connor C. Baham and Connor D. Some other combination of students 35. log π₯ + log(π₯ + 4) is equal to: A. B. C. D. log(2π₯ + 4) log(π₯ 2 + 4π₯) log(π₯ 2 + 4) log(π₯) log(π₯ + 4) 36. log(π₯ 2 − 4) − log(π₯ − 2) is equal to: A. log(π₯ + 2) B. log(π₯ 2 − π₯ − 2) C. log(π₯ − 2) D. log(π₯ 2 −4) log(π₯−2) 37. (log 2π₯)2 is equivalent to: A. B. C. D. 2 log 2π₯ log 4π₯ 2 2 log 4π₯ (log 2)2 + 2 log 2 log π₯ + (log π₯)2 1 38. The expression 3 log π₯ 4 + log π₯ 8 − 4 log π₯ 16, where π₯ > 0. Is equal to: A. log π₯ 384 B. 3 4 log π₯ 512 C. log π₯ 256 D. 1 4 1 log π₯ (2) 39. log π (π6 π 2 ) − log π (π2 π 2 ) is equivalent to: A. B. C. D. 3 4 4p p4 40. If log 3 π΄ = π‘, then log 3 27π΄3 = A. B. C. D. 3 + 3π‘ 3 + π‘3 9π‘ 3π‘ 3 1 41. If log 3 π₯ 2 = 2 and 2 log π √π₯ = 3, then the value of k is _____. 42. The graph of π¦ = log π₯ is transformed to the graph of π¦ = log(2π₯ + 5) by a horizontal stretch about the y-axis by a factor of p followed by a horizontal translation of q units left. The value of p + q is: A. B. C. D. 3 4.5 5.5 7 43. An equation of the asymptote of π¦ = 3 log 4 (π₯ + 2) − 6 is: A. B. C. D. π₯ = −6 π¦ = −6 π₯ = −2 π¦ = −2 44. The graph of π¦ = log 7 π₯ is reflected in the x-axis, the equation of the image can be written in the form π¦ = log π π₯. The value of c, to the nearest hundredth, is ____. 45. A current, πΌπ amperes, falls to πΌ amperes after t seconds according to the formula πΌ = πΌπ π −ππ‘ . The value of the constant, k, to the nearest whole number, if a current of 25 amperes falls to 2.5 amperes in 0.01 seconds is ______. 46. Kyle determined the exact solution to the exponential equation 52−π₯ = 2. He wrote the answer as the quotient of 2 logarithms in the form log π log 5 . The value of M is ____. 47. A student invests $100 @ 8% per year compounded semi-annually. The amount of money that the student will have at the end each year is increased from the amount at the end of the previous year by a factor of: A. B. C. D. 1.04 1.08 1.0816 1.16 48. George invested $2500in an account which pays compound interest of 8.1% per annum compounded quarterly. The number of quarters it will take George’s investment to at least double in value is ________. 49. The tripling period, to the nearest tenth of an hour, of a bacteria culture which grows from 500 cells to 64000 cells in 50 hours is _____. 50. Radioactive decay material decays to 40% of its original mass in 5 years. The half-life of the radioactive material, to the nearest hundredth of a year, is ____. Answer Key: 1) A 2) C 3) A 4) B 5) 5.0 6) 0.36 7) 1.2 8) C 9) D 10) D 11) B 12) C 13) A 14) A 15) C 16) B 17) A 18) 3124 19) 2 20) B 21) A 22) D 23) A 24) A 25) C 26) B 27) D 28) 3.0 29) 729 30) D 31) 7.0 32) 313 33) 4.29 34) B 35) B 36) A 37) D 38) C 39) B 40) A 41) 27 42) A 43) C 44) 0.14 45) 230 46) 12.5 47) C 48) 35 49) 11.3 50) 3.78