$x^2-7x+30$

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

$3\sin^3\left(x\right)\csc\left(y\right)+\cos^2\left(x\right)+2\cos\left(-x\right)\cos\left(x\right)$

$\left(y-yx^2\right)\frac{dy}{dx}=\left(y-1\right)$

$\lim_{x\to3}\left(\frac{7x^2-10x-3}{x-4}\right)$

$6n+8n^3+9n-n^2+n^3$

$x^2-625$