$7x^5-2x^3+\:x$

$\frac { a ^ { 3 } - \frac { 1 } { 2 } a ) ^ { 2 } } { 1 }$

$\frac{dy}{dx}+x=0$

$\lim_{x\to0}\left(\frac{\left(sec\left(x\right)e^{3x}-1\right)}{x}\right)$

$\left(2-3x\right)\left(1+x\right)\left(x+2\right)$

$8mn^2\:2mn-3n^2$

$\frac{du}{dx}=\frac{1}{\left(u-x\right)}$