10.7.29 Calculating integrals of a real variable using residues
condition: Calculate the integral using residues: \[ \int_{-\infty}^{\infty} \frac{\cos 3 x d x}{\left(x^{2}+4\right)^{2}} \]
Here you can find calculations of proper and improper integrals of a real variable using residues, using various techniques.