Solution

ID: past-exam-of-the-mathematics-course-of-the-university-of-cambridge/2024/ia/paper-1/10e/c/ii/solution

No. At , let
The function is differentiable at , and
so the composite has derivative one at zero. But
is unbounded, so is not differentiable. This is a nondifferentiable inner function with a differentiable nondegenerate composite.

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