Question

How do you find the average rate of change of `f(x)= 3x^2 - 2x` over interval [1,2]?

Answer 1

7

Explanation:

The average rate of change is found using

`color(red)(|bar(ul(color(white)(a/a)color(black)( (f(b) - f(a))/(b - a))color(white)(a/a)|)))`

In the interval [1 , 2 ] , a = 1 and b = 2 ( from left to right )

`rArr (f(2) - f(1))/(2 - 1) " is required to be calculated "`

f(2) `= 3(2)^2- 2(2) = 8`

and f(1) =3 - 2 = 1

`rArr" average rate of change " = (8-1)/1 = 7`