Section 5.1 Extra Practice STUDENT BOOK PAGES 227–234 1. Determine the derivative of each of the following. a. f (x) ⫽ 5e 4x e 6x ⫹ e 20 b. f (x) ⫽ 2 x c. f (x) ⫽ 12e 3 d. f (x) ⫽ 2e 3x ⫹1 2 e. f (x) ⫽ e x ⫹3x 2 f. f (x) ⫽ e (x⫺2) Copyright © 2009 by Nelson Education Ltd. 2. For each function, determine the value of the derivative f ⬘(a) for the given value of a. a. f (x) ⫽ x 2 ⫹ e 2x, a ⫽ 4 e 4x b. f (x) ⫽ , a ⫽ 1 42 c. f (x) ⫽ e 3x ⫺8x⫹1, a ⫽ 3 4 5 d. f (x) ⫽ e x , a ⫽ 0 5 2 e. f (x) ⫽ e (x⫹1) , a ⫽ 2 3 ex f. f (x) ⫽ ⫺3x , a ⫽ 1 e 3. Find the slope of the line tangent to y ⫽ e x for each of the following values of x. a. x ⫽ ⫺1 b. x ⫽ 1 c. x ⫽ 2 d. x ⫽ 0 2 5. Determine y⬘, y⬙ and y for the following functions. a. y ⫽ 6e ⫺x x2 ⫹ 1 b. y ⫽ e 2 x c. y ⫽ e 2 d. y ⫽ (e x ⫹ 1) 2 6. For each of the following functions, determine the points at which the tangent line is horizontal, if any such points exist. 3 a. f (x) ⫽ e x b. f (x) ⫽ e ⫺2x x c. f (x) ⫽ 4e 2 2 d. f (x) ⫽ e (x ⫹5) e. f (x) ⫽ 2xe 2x 7. The population, P, of bacteria in a sample at time t (in hours) can be expressed by t P(t) ⫽ 5000A20 ⫹ e⫺30 B. a. What is the initial population of bacteria? b. What is the rate of change at time t? c. What is the rate of change at time t ⫽ 5? d. What is the rate of change at time t ⫽ 20? ⫺1 4. Determine the equation of the line tangent to each of the functions at the point where x ⫽ a. 3x a. f (x) ⫽ e⫺ 2 , a ⫽ 2 2 b. f (x) ⫽ 8e x , a ⫽ 1 2 c. f (x) ⫽ x , a ⫽ ⫺1 e 2 d. f (x) ⫽ e (x ⫹x), a ⫽ 0 ⫺2 e. f (x) ⫽ e x , a ⫽ 2 f. f (x) ⫽ 10 ⫹ e x, a ⫽ 10 Section 5.1 Extra Practice 387