$\left(y-x^3\right)dx\:+\:\left(x+y^3\right)dy\:=\:0$

$\int\left(\frac{\left(\ln\left(x\right)\right)^4}{5x}\right)dx$

$5x^4\left(x^2-2x\right)$

$\frac{1+\cos\left(x\right)}{1-\sin\left(x\right)}=\left(\tan\left(x\right)\right)^2\left(\frac{1+\sin\left(x\right)}{1-\cos\left(x\right)}\right)$

$cos^2\theta\:\left(tan^2\theta\:\:+1\right)=1$

$\frac{t^2-2t-3}{t^2-t-2}$

$\left(x+2\right)\left(x-2\right)\left(2x+2\right)$