# I understand the conditions under which a function is differentiable. Is there a function, let's say f(x), for which we cannot find a derivative? If so, what is an example of such a function? Thank you in advance.

Question

I understand the conditions under which a function is differentiable.

Is there a function, let's say f(x), for which we cannot find a derivative?

If so, what is an example of such a function?