### Home > CALC > Chapter 3 > Lesson 3.4.2 > Problem 3-164

3-164.

Notice that the clues describe *f* '(*x*), yet you are asked to sketch *f*(*x*).

*f* '(*x*) > 0 on 1 < *x* < 4

Translate: *f*(*x*) is increasing between *x* = 1 and *x* = 4.

*f* '(*x*) < 0 on *x* < 1 and *x* > 4

Translate: *f*(*x*) is decreasing before *x* = 1 and after *x* = 4.

*f* '(*x*) = 0 for *x* = 1, *x* = 4

Translate: *x* has reached a local maximum or local minimum at *x* = 1 and *x* = 4.