Average rate and instantaneous rate?
Hi everyone! :) I happen to be stumped on this question below.
A function y=f(x) and values of x0 and x1 are given.
y= x^3 , x0= 1 , x1= 2
a. Find the average rate of change of y with respect to x.
b. Find the instantaneous rate of change of y with respect to x at x0.
For a. I got 7 as my answer. I'm curious what everyone else gets. For b. I am stumped and know that you have to find a limit probably. Showing steps would be appreciated as I'd like to see how this is done.
(NOTE: We are not allowed to use derivatives yet, so it all has to be limits and stuff.)