If we check for their
differentiability, we find that they are all differentiable for all the values of x This
makes us to believe that the generalisation “Every continuous function is differentiable”
may be true But if we check the differentiability of the function given by “φ(x) = | x|”
which is continuous, we find that it is not differentiable at x = 0 This means that the
statement “Every continuous function is differentiable” is false, in general