Question

How do you find the average rate of change of `h(t) = t^2 + 4t` over the interval [-1,2]?

Answer 1

h(-1) `= -3`
h(2) `= 12`
Average rate of change `= (12-(-3))/(2-(-1)) = 15/3 = 5`

Explanation:

First values for f(-1) and f(2) should be found.
h(-1) `= (-1)^2 + 4(-1) = 1-4 = -3`
h(2) `= 2^2 + 4(2) = 4 + 8 = 12`

Then the formula below can be filled in accordingly.
Average rate of change `= (Deltaf(x))/(Deltax) = (f(2) - f(-1))/(2-(-1)) = (12-(-3))/(3) = 15/3 = 5`