Question

What is the average rate of change of the function f(x)=2x^2+x+5 over the interval -2<x<2?

A. -4
B. -1
C. 1
D. 4​

Answer 1

D 1 is the correct answers

Answer 2

C

Explanation:

The average rate of change of f(x) in the closed interval [ a, b ] is

`(f(b)-f(a))/(b-a)`

Here [ a, b ] = [ - 2, 2 ] , then

f(b) = f(2) = 2(2)² + 2 + 5 = 8 + 2 + 5 = 15

f(a) = f(- 2) = 2(- 2)² + (- 2) + 5 = 8 - 2 + 5 = 11 , then

average rate of change =
`(15-11)/(2-(-2))` =
`(4)/(4)` = 1 → C