Question

How do you find the average rate of change of `f(x) = 5x^2+2x-7` over the interval [5,7]?

Answer 1

`62`

Explanation:

`"the average rate of change of " f(x) " is"`

`(f(7)-f(5))/(7-5)larr(f(b)-f(a))/(b-a)to[a,b]=[5,7]`

`f(7)=5(7)^2+2(7)-7=252`

`f(5)=5(5)^2+2(5)-7=128`

`rArr"average rate of change "=(252-128)/(7-5)=62`