Thread: Derivative of an absolute value

How do I find f'(x) of f(x) = |x+3| -1?

Originally Posted by unluckykc

How do I find f'(x) of f(x) = |x+3| -1?

Hello,

write f without absolute values:



Now you can calculate the derivative



Since x has the coefficient 1 in your original equation the derivative could be only 1 or -1. You only have to determine the point where the slope is changing: The zeros of the absolute value.