$\frac{\sin\left(x\right)+\sin\left(20\right)}{1+\cos\left(x\right)+\cos\left(2x\right)}$

$3\sin^2x\:=\:-\sin\left(x\right)$

$4c+\left(-c\right)+4+\left(-1\right)$

$\frac{d^2y}{dx^2}+\frac{dy}{dx}+5y=35e^{-4x}\:$

$5x^2+6+8-7^2$

$\left(p^2\right)^5$

$\frac{dy}{dx}=\frac{xy+2y-3x-6}{xy-3y+x-3}$