### Home > CALC > Chapter 5 > Lesson 5.2.2 > Problem 5-68

5-68.

Describe how to find the derivative for *f*(*x*) = *g*(*ax* + *b*), where *a* and *b* are constants. Check by using your derivative on *f*(*x*) = cos(3*x*). Homework Help ✎

Both of these functions are composites and require the Chain Rule to derive. Start by comparing each function to *f*(*x*) + *g*(*ax* + *b*).

Then explain how the Chain Rule works.