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1. The problem statement, all variables and given/known data

Suppose f:(a,b) -> R is differentiable and | f'(x) | <= M for all x in (a,b). Prove f is uniformly continuous on (a,b).

2. Relevant equations

The definition of uniform continuity is:

for any e there is a d s.t. | x- Y | < d then | f(x) -f(y | < e.

3. The attempt at a solution

Intuitively, if f is differentiable it is continuous. If its derivative is bounded it cannot change fast enough to break continuity. The interval is bounded, and the function must be bounded on the open interval. It seems that there is not way that the function cannot be uniformly continuous. But how do I say that? Or am I on the wrong track altogether.

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# Homework Help: Differentiable and uniformly continuous?

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