$\left(\frac{1}{2}m^3-5n^4\right)^3$

$n\:=\:\left\{\left(-2\right)^n\right\}\:n^3\:0$

$-6\cdot6\cdot6\cdot n^3\cdot n^3\cdot n^3\cdot b^4\cdot b^4\cdot b^4$

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

$\int\frac{\cos x}{\text{senx}}\cdot\tan xdx$

$12x+3y-5x+15y$

$20^3\cdot20^{-3}$