Algebra II Chapter 8 Test (A) Show all your work for full credit. Name___________________ Date___________________ Period__________________ For questions 1-4, let f ( x) x 2 5 and g ( x) x 7 . Perform each function operation. 1) f ( x) g ( x) 1)_________________(1) 2) ( f g )( x) 2)_________________(2) 3) f ( x) g ( x) 3)_________________(2) g ( x) 4) f ( x) 4)________________(1) A new car that sells for $20,000 depreciates 15% each year. 5)Write a function that models the value of the car. 5)____________________(3) 6) Find the value of the car after 3 years. 6)______________(2) For 7 and 8, let f ( x) 3 x 5 and g ( x) x 2 1 7) find f g (2) 7)______________(3) 8) find g ( f (1)) 8)______________(3) For the function f(x) = 2x + 4, 9) Graph f(x) (1 pt) 10) Find its inverse, f 1 11) Graph f 1 (1 pt) 12) Is f 1 a function? 10) f 1 _____________(2) 12) _________________(1) For 13, identify whether the function represents exponential growth or exponential decay 13) .05(1.09) x 13)_____________(1) 14) Graph this function. Clearly label at least 3 points. y 3(2) x (4 pts) For the following function, identify the parent function and what transformations you would make to the parent function. y 3 x 1 15) Parent function:_____________(1) 16)Transformations:______________ _________________________(2) 17) Horizontal asymptote of the transformed function: _______________(1) 18) If you invest $200 in a continuously compounded account at an interest rate of 7%, how much will you have after 10 years? 18)_________________(3) Write this equation in logarithmic form 19) 25 625 2 19)___________________(1) Evaluate this logarithm 20) log 5 25 20)__________________(2) 21) Graph this logarithmic function. Clearly label at least 3 points. y log 5 ( x 3) (4 pts) Write this logarithmic function as a single logarithm. 22) 5 log 2 + 2 log 2 22)___________________(3) Expand this logarithm. y2 23) log z 23)________________________(3) Use the properties of logarithms to evaluate this expression. 24) log 8 4 log 8 16 24)___________________(3) Solve each equation. Round to the nearest hundredth. 25) log( 7 x 3) 2 25)_________________(3) 26) 2 log x log 5 2 26)________________(3) 20 27)_________________(3) 27) 7 3x 28) ln x ln 2 3 28)_________________(3) Use the change of base formula to rewrite each expression using common logarithms. 29) log 4 12 29)________________(1) Extra credit (2 points): A culture of 10 bacteria is started, and the number of bacteria will double every hour. In about how many hours will there be 3,000,000 bacteria? Extra credit (1 point): Ellie lives on the nineteenth floor of an apartment building. Whenever she gets into the elevator on the first floor, she presses the button for the fourth floor, where she gets out and walks the rest of the way up. When she leaves her apartment, however, she takes the elevator all the way down. Since she would rather ride than walk, why does she do that?