$18+x^2-6x=0$

$\lim_{x\to0}\left(\frac{x-3-\sqrt{5}}{x}\right)$

$x^3\cdot8x^3$

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

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

$\left(2\:+\:ab\right)\left(4\:-\:2ab\:+\:a^2b^2\right)$

$\frac{5csc\left(x\right)}{csc\left(x\right)-cot\left(x\right)}=5csc\left(x\right)\left(csc\left(x\right)+cot\left(x\right)\right)$