$\int_{0}^{1}\frac{1}{\left(x+1\right)\left(x^2+1\right)}dx$

$\int\frac{dx}{x^2+7x-6}$

$\int_2^{\infty}\left(\frac{1}{x^2+x-2}\right)dx$

$\int_{-\infty}^{\infty}\left(\frac{1}{2x^2\left(x-1\right)}\right)dx$

$\int_0^{\infty}\left(\frac{1}{\sqrt{x}+x^2}\right)dx$

$\int\frac{1}{\left(x^4+1\right)}dx$

$\int_{-1}^2\frac{xdx}{x^2+4}$

$\int\frac{dx}{x^2+7x+6}$