Solve Residue Integrals Easily with Our Residues Homework Help

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The discussion focuses on solving the integral from 0 to infinity of the function x² / (x⁶ + 1), which equals π/6. Participants emphasize the importance of recognizing the symmetry of the function on the real axis and the need to identify poles for effective contour integration. A suggestion is made to avoid integrating over the half circle and instead return along the line z = r exp(i π/3), which simplifies the process of summing the three poles in the upper half-plane.

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Homework Statement



show [tex]^{\infty}_{0}\int[/tex] x2 / (x6 + 1) = [tex]\pi[/tex]/6


Homework Equations





The Attempt at a Solution



= 1/2 [tex]\int^{\infty}_{-\infty}[/tex] ...

I am not sure how to go about this any pointers pls?
 
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you're really supposed to attempt some working

but note the function is symmetric on the real axis... and the magnitude will get small as the radius gets big, this should help you pick a contour to integrate

it will help to find the poles as well...
 


Note that you don't need to integrate over the half circle and come back along the negative real axis. You would then have to sum over the three poles in the upper half plane. Instead, you can return along the line z = r exp(i pi/3).
 

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