i'm looking at this, but dont really know how to approach this. determine where the function x|x| is differentiable and find the derivative. i'm looking at this, but just have no idea where to start? I mean, I know x is differentiable everywhere, and |x| is not differentable at 0. looking at this, I'm thinking about the product rule, and i'm tryint to see if I need to solve this using epsilon delta method, but have no idea. any clues just on how to solve these types of problems? and another one: g(x) = x^2/xin(1/x^2) for x != 0 and g(0) = 0. I'm suppose to show that g is differntaible everywhere. how do I show these types of problems??