Choose the correct answer.
The set of points where the function f(x) = x|x| is differentiable is
We have f(x) = x|x|
Where
We have –x2 and x2 which being polynomial functions are continuous and differentiable.
The only possible point of non-differentiability can be x =0.
LHD at x =0,
RHD at x =0,
∵ LHD = RHD = f(0)
∴ f(x) is differentiable at x =0.
Hence f(x) is differentiable at (–∞, ∞).