Do you really need "contour" here? (2)
Calculus
Level
4
\[\large \int_{-\infty}^{\infty} \dfrac{\cos x}{1+x^{2}} \, dx\]
Find the value of the closed form of the above integral.
Give your answer to 3 decimal places.
Bonus:
Solve this question without using contour integration.
Generalise \(\displaystyle \int_{-\infty}^{\infty} \dfrac{\cos(x)}{a^{2}+x^{2}} dx\), where \(a\) is a constant.
by
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