### Home > APCALC > Chapter 4 > Lesson 4.4.1 > Problem 4-137

4-137.

Graph , given below, and determine if

*is differentiable at*

*.*

Differentiability implies continuity. If you are checking for differentiability, you also need to check for continuity.

To check for continuity:

is continuous at

*.*

To check for differentiability:

Since both and

*are continuous at*

*.*