Question

Find the average rate of change of f(x)=2x^2-7x from x=2 to x=5

Answer 1

7

Explanation:

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

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

Here [ a, b ] = [2, 5 ]

f(b) = f(5) = 2(5)² - 7(5) = 50 - 35 = 15

f(a) = f(2) = 2(2)² - 7(2) = 8 - 14 = - 6, thus

average rate of change =
`(15-(-6))/(5-2)` =
`(21)/(3)` = 7