# Math Help - Differentiating with modulus function

1. ## Differentiating with modulus function

Where is the function h(x) = |x 􀀀- 1| + |x + 2| differentiable?

(a) Give a formula for h'(x).

(b) Sketch the graphs of h and h'

2. ## Re: Differentiating with modulus function

Originally Posted by Vishak

Where is the function h(x) = |x 􀀀- 1| + |x + 2| differentiable?

(a) Give a formula for h'(x).

(b) Sketch the graphs of h and h'
The function will be differentiable everywhere except the cusps. Where are these?

3. ## Re: Differentiating with modulus function

I think at x = 1 and x = -2. Do I have to split the function to find h'(x)?

4. ## Re: Differentiating with modulus function

Yes on both counts