The problem is [tex]\int _{-\infty}^\infty \frac{x-sinx}{x^3} dx [/tex](adsbygoogle = window.adsbygoogle || []).push({});

The answer is pi/2.

Contour integration is to be used.

Here are my questions about the method:

Is the contour a semicircle with a bump?

There is no z^-1 term in the expansion, so the residue at the origin is zero?

Jordan's lemma=> large radius contribution ->0?

So where does the actual contribution come from?

thanks

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# Homework Help: Integral of (x-sinx)/x^3 (contour integration)

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