Can You Solve This Advanced Definite Integral Using Residue Theorem?

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SUMMARY

The discussion centers on solving the integral $$ \int_0^\infty \frac{dx}{\left\{x^4+(1+2\sqrt{2})x^2+1 \right\}\left\{x^{100}-x^{99}+x^{98}-\cdots +1\right\}}=\frac{\pi}{2(1+\sqrt{2})}$$ using the residue theorem. The integrand is expressed as [\ (x-\alpha i)(x+\alpha i)(x-\beta i)(x+\beta i)\prod_{j=1}^{100}(x+e^{\pi i (\frac{2j}{101})})\ ]^{-1}, where the parameters α and β are derived from the quadratic equation y^2+(1+2\sqrt{2})y+1=0. The challenge lies in identifying an appropriate contour for applying the residue theorem.

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sbhatnagar
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This is classic one. Prove that

$$ \int_0^\infty \frac{dx}{\left\{x^4+(1+2\sqrt{2})x^2+1 \right\}\left\{x^{100}-x^{99}+x^{98}-\cdots +1\right\}}=\frac{\pi}{2(1+\sqrt{2})}$$
 
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Residue theorem cound be applicable. The integrand is
[\ (x-\alpha i)(x+\alpha i)(x-\beta i)(x+\beta i)\prod_{j=1}^{100}(x+e^{\pi i (\frac{2j}{101})})\ ]^{-1}
where for ##0< \alpha < \beta ## , ##-\alpha^2## and ##-\beta^2## are solutions of quadratic equation,
y^2+(1+2\sqrt{2})y+1=0
But I have not found an appropriate contour. 
 
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