Oh come on. Surely you know this.
Find where g(x) is NOT differentiable.
I know that functions arnt differentiable at corner points or points of vertical tangency...but how do i go on about finding the actual values where they are not differentiable??
In general, you can always draw a graph of f(x) then reflect in the x-axis the parts lying below the x-axis to get |f(x)|.
The 'corners' (I personally prefer calling them the 'pointy bits'. Their technical name is salient points) are then obvious and will be x-intercepts. But note that not all x-intercepts will be 'corners' ..... (for example, in your present question x = 0 is NOT a corner).