Where is the function F(x)=|x| increasing?

Question

Advanced functions math

Answer 1

f(x) = |x| means:

 

            ⌈   x  if x ≥ 0

f(x) = <

            ⌊  -x  if x < 0

 

So when x ≥ 0, f(x) has a slope of +1 and is thus increasing.  When x < 0, f(x) has a slope of -1 and is thus decreasing.