$\int\frac{\left(x+11\right)}{x^2-3x-4}dx$

$\left(y^2e^{xy^2+4x^3}\right)dx+\left(2xye^{xy^2}\right)dy=0$

$\frac{d^2}{dx^2}\left(\cos\left(7x\right)\right)$

$\frac{dy}{dx}+y=\frac{1}{3}$

$2\cos\frac{\pi}{4}\:x=1$

$tanx\left(cotx+cscx\right)$

$\int x^2\cdot\left(x+9\right)^{-\frac{1}{2}}dx$