$6+12-3\cdot2\cdot\frac{8}{-1}$

$\left(a^6+8\right)\left(a^6-3\right)$

$x^2-9x=36$

$\frac{d}{dx}\left(y=\left(2\cdot x\cdot v\right)+\left(y^2+v^3\right)\right)$

$\lim_{x\to0}\left(\frac{1-\cos\left(x\right)}{2-sin^2x}\right)$

$\lim_{x\to0}\left(\frac{e^{-x}}{ln\left(1\:+\:e^{-x}\right)}\right)$

$1-\frac{\cos^2a}{1+\text{sina}}=\text{sina}$