### Home > APCALC > Chapter 7 > Lesson 7.1.3 > Problem 7-31

7-31.

If Hoi Yin’s hair is of length , and

*represent time, explain what*

Is it positive or negative? Homework Help ✎

The derivative represents instantaneous slope (growth). Is the length of Hoi Yin's hair growing at a positive or negative rate?