$6p+2p-18$

$9-\left\{6-\left[\left(-32\:-\:15\:+8\right)-22\:\right]-7\right\}$

$\int\frac{x^2+2x-6}{x\left(x+1\right)\left(x-1\right)}dx$

$\left(5x\right)^2+13\left(5x\right)+42$

$x^2\cdot\frac{1}{x}=x^2\cdot\frac{6}{x^2}$

$\lim_{x\to\infty}\left(\frac{2^x}{x^4-x+1}\right)$

$5ab+3ab-2ab$