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Is the function $f(x)=\sin(1/x)$ Lebesgue integrable on $(0,1]$?

I know that, as $f$ is continuous on the set, it is a measurable function. However, I'm stumped on how to go on. A nudge in the right direction would be greatly appreciated.

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  • $\begingroup$ It is even Riemann integrable. $\endgroup$ Commented Feb 10, 2015 at 11:17
  • $\begingroup$ Does Riemann imply Lebesgue on finite intervals then? $\endgroup$
    – Ori
    Commented Feb 10, 2015 at 11:19
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    $\begingroup$ Yes $\endgroup$ Commented Feb 10, 2015 at 11:27

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Hint: $|f(x)|\le1$ for all $x\in(0,1]$, so $f$ is uniformly bounded.

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  • $\begingroup$ Thanks, I can't believe I missed something so obvious. $\endgroup$
    – Ori
    Commented Feb 10, 2015 at 11:15
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    $\begingroup$ What does it mean for a single function to be uniformly bounded? $\endgroup$ Commented Feb 10, 2015 at 11:20
  • $\begingroup$ Yeah alright, "bounded" was probably enough. $\endgroup$
    – Jason
    Commented Feb 10, 2015 at 12:02

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