Given f(x) is continuos at x0, for f(x) to be differentiable at x0, the left hard Derivative and the right hand Derivative must exist finitely.
False
For f(x) to be differentiable at x0, the
LHD,lim△x→0f(x+△x)−f(x)△x and
RHD,lim△x→0f(x+△x)−f(x)△x must be finite and equal.
For example, the graph f(x) has LHD and RHS are not equal.
Intestively whenever there is a sharp ede on f(x) the LHD and RHD are not equal and f(x) wont be
differentiable at x0 even though given f(x) is continuous