$\left(7x^3y^2-4\right)\left(7x^3y^2+7\right)$

$-9\:-\:\frac{20}{-5}$

$-4\cdot3\cdot5+2\cdot8-3\cdot7$

$\frac{4y-2y}{2xy}$

$\left(3y^2+x\:cos\:xy\right)\frac{dy}{dx}+\left(3x^2+y\:cos\:xy\right)=0$

$\lim_{x\to\infty}\left(\frac{e^{3x}-1}{3x^2+2x}\right)$

$f^{6}-100$