`f(x) = 5 - | x- 5|` Find the critical numbers, open intervals on which the function is increasing or decreasing, apply first derivative test to identify all relative extrema.

Textbook Question

Chapter 3, 3.3 - Problem 31 - Calculus of a Single Variable (10th Edition, Ron Larson).
See all solutions for this textbook.

1 Answer | Add Yours

shumbm's profile pic

Borys Shumyatskiy | College Teacher | (Level 3) Associate Educator

Posted on

This function is continuous everywhere and is differentiable everywhere except x=5.

For x<=5, f(x)=x, f'(x)=1 and for x>-5 f(x)=10-x, f'(x)=-1. So there are no points for which f'(x)=0, and x=5 is the only critical point.

The function f is increasing on `(-oo, 5)` and is decreasing on `(5, +oo)` . So x=5 is a relative maximum.

We’ve answered 319,630 questions. We can answer yours, too.

Ask a question