Question

Determine the average rate of change of the function f(x)=-2x^2+5 over the interval from x=1 to x=4.

My choices are:
-10
10
-8
8
None of the others

Answer 1

Do I plug this in like this:

-2(1)^2+5=3
-2(4)^2+5=-27

Answer 2

yes that's a start. You found f(1) = 3 and f(4) = -27. So now you do
\[\frac{ -27-3 }{ 4-1 }\]because the equation is\[avg~rate~of~change=\frac{ f(b)-f(a) }{ b-a }\]

Answer 3

oh ok I got -10 thank you for explain that with the formula.

Answer 4

yeah that's right. you're welcome