$\int_{-\infty}^0\left(\frac{2x^3}{\left(x^2+1\right)^2}\right)dx$

$\left(5x^3-3\right)^2$

$\left(n^x-8\right)\left(n^x+8\right)$

$\frac{y^2}{y-3}\cdot\frac{-1}{\left(y+2\right)}$

$8x^{18}-729y^3z\:15$

$\int_1^4\left(\frac{1}{4}e^{\frac{-t}{4}}\right)dx$

$3x+2y-8x-8y$