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

$\frac{dy}{dx}=\frac{e^{-x-y}}{y}$

$\left(\frac{dy}{dx}\right)=2x$

$\lim_{x\to\infty}\left(\frac{9e^{\sqrt{\ln\left(x\right)}}}{\sqrt{x}}\right)$

$n^2+n+56$

$\left(x-y+3z\right)\left(x-y-7z\right)$

$\frac{6x^2y^{-3}}{2x^{-4}y^{-5}}$