$\frac{1-2-2-3}{2}$

$18c+9$

$\left|-8\right|+\left|12\right|$

$\int\frac{4x-1}{\left(x+3\right)\left(x-2\right)\left(x+1\right)}dx$

$\:\lim\:_{x\to\:\:3}\left(\frac{x^3-3x^2+2x-6}{2x-4}\right)$

$\left(9x^4y^2-12z\right)\left(9x^4y^2+12z\right)$

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