Determine whether the following two functions are differentiable at the given value
a) f(x) = xsin(1/x), f(0)=0: at given value 0
f(x) = 1-x if x<1
x(1-x) if x>= 1 at given value 1
I think a is differentiable. I found the difference quotient and found that as
h->0 the limit of the quotient -> 0 also.
But I can't seem to get started on b!