Let f(x)=8x^2. Find a value A such that the average rate of change of f(x) from 1 to A equals 96.
someone help me please
Hello.
The rate of change from $\displaystyle a$ to $\displaystyle b$ is equal to:
$\displaystyle \frac{f(b)-f(a)}{b-a}$
So in your problem, you'd set 96 equal to that. What are $\displaystyle a$ and $\displaystyle b$ in your problem? For that matter, what are $\displaystyle f(a)$ and $\displaystyle f(b)$?
It's okay, don't feel bad. But $\displaystyle b$ is A, and $\displaystyle a$ is 1. $\displaystyle f(b) - f(a)$ means f(A) - f(1)... in this case, $\displaystyle 8A^2 - 8$. Put that over $\displaystyle b - a$. (Which is, in this problem... ??) You're almost there!