👉 A function f(x) is said to be non-differentiable at x = a if its derivative with respect to x at x = a is equal to zero. This means that for any value of x that satisfies the condition, f'(x) = 0. In calculus, this concept is fundamental in understanding how functions behave as they approach a particular point or when a function is applied to a specific range of values. By defining a non-differentiable function at a point, we can
