$\left(x\:+\:y\right)\left(\:x\:2\:-\:xy\:+\:y\:2\:\right)$

$2-\left|-5-2\left(-1-2+6-1\right)\right|-4\cdot\left(-3+5\right)$

$588+807$

$\int\frac{4\sqrt{x^2-9}}{x^3}dx$

$2-2\left(x+6\right)<2+x$

$-4x+1=21$

$\frac{2}{3}x^2+\frac{2}{1}y^3\cdot\frac{2}{3}x^2-\frac{2}{1}y^3$