$2\:x\:2\:+\:6x\:+\:8\:x\:3\:-\:12\:x\:4$

$\left(9t+1\right)\left(9t-1\right)$

$\frac{\left(1+tany\right)dy}{dx}=x^2+1$

$\frac{4}{m^2-1}+\frac{2}{m-1}+\frac{m}{m+1}$

$\lim_{x\to\infty}\sqrt{x^2+6x+3}-x$

$\cos\left(\arccos\left(u\right)\right)$

$\frac{\left(x+1\right)\left(x+2\right)^2}{\left(x+3\right)\left(x+4\right)}$