Question

F(x) = |x − 1| find the derivative from the left at x = 1. if it does not exist, enter none.

Answer 1

Given:  f(x) = |x - 1|

A graph of the function is shown below.
The function is either
f(x) = x-1, for x>1
or
f(x) = 1-x, for x<1

Therefore
f'(x) = 1, for x>1
and
f'(x) = -1, for x<1

Answer: -1