$dy=x^4y^2dx$

$\left(a^2-z^2\right)\left(7a^2+2x^2\right)$

$\sec^4\left(a\right)-\tan^4\left(a\right)=1+2\tan^2\left(a\right)$

$\int\left(\frac{1}{r}\right)\:dr$

$-500+270-380-750+330$

$\frac{6}{x^2-2x-8}$

$-\:54a^2b^3+\left(-35a^2b^3\right)-\left(-18ab^2\right)+\left(-\left(-52ab^2\right)\right)$