### Home > PC3 > Chapter 9 > Lesson 9.1.4 > Problem9-91

9-91.

This problem is a checkpoint for average and instantaneous rates of change.

Let $f(x) = 3x^2 − 4$.

1. Calculate the average rate of change from $x = 10$ to $x = 12$.

2. Calculate the average rate of change from $x = 11$ to $x = 11 + h$.

3. Evaluate the expression in part (b) as $h → 0$. What does this tell you about the function at $x = 11$?

4. Calculate the instantaneous rate of change at $x = 1$.