Question

Given the function f(x)=x^2-4x-1 determine the average rate of change of the function over the interval -4

Answer 1

Answer:

- 1

Step-by-step explanation:

The average rate of change in the closed interval [ a, b ] is

$\frac{f(b)-f(a)}{b-a}$

Here [ a, b ] = [4, 7 ], thus

f(b) = f(7) = 7² - 4(7) - 1 = 49 - 28 - 1 = 20

f(a) = f(- 4) = (- 4)² - 4(- 4) - 1 = 16 + 16 - 1 = 31

average rate of change = $\frac{20-31}{7+4}$ = $\frac{-11}{11}$ = - 1