$\int\frac{-3x-1}{x^2-x}dx$

$\frac{a^{2}+a-42}{a^{2}-a-30}$

$\left(x+y\right)^2+9z^2+62\left(x+y\right)$

$\lim_{x\to1}\left(\frac{1-x+ln\left(x\right)}{1+\cos3\pi x}\right)$

$\frac{\sin^2x}{\sec\left(x\right)+1}=\frac{1-\cos\left(x\right)}{\sec\left(x\right)}$

$\frac{4x^3-5x^2-2x+1}{x-1}$

$\:4x^2+7\le0$