Bounded derivative Riemann integrable

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SUMMARY

The discussion centers on the question of whether a bounded derivative of a differentiable function is necessarily Riemann integrable. It is established that a function f:[a,b]→ℝ being differentiable does not guarantee that its derivative f' is Riemann integrable. The counterexample provided is Volterra's function, which demonstrates that boundedness alone does not imply Riemann integrability. The user expresses difficulty in constructing a counterexample based on the function x²sin(1/x) and understanding the relevant Wikipedia explanations.

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jostpuur
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Assume that a function f:[a,b]\to\mathbb{R} is differentiable in all points of its domain, and that the derivative f':[a,b]\to\mathbb{R} is bounded. Is the derivative necessarily Riemann integrable?

This what I know:

Fact 1: Assume that a function is differentiable at all points of its domain. Then the derivative is not necessarily Riemann integrable.

Fact 2: Assume that a function is bounded. Then the function is not necessarily Riemann integrable.

So my question is not obvious.
 
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jostpuur said:
Assume that a function f:[a,b]\to\mathbb{R} is differentiable in all points of its domain, and that the derivative f':[a,b]\to\mathbb{R} is bounded. Is the derivative necessarily Riemann integrable?

No: Volterra's function is a counterexample.
 
It is unfortunate that I cannot prove to you my honesty, but I swear that I came up with this question on my own, and was also attempting to construct a counter example with the x^2\sin (\frac{1}{x}) as basis!

But I was unable to get a counter example working.

Actually I think I'm also unable to understand the explanation on Wikipedia page.
 
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