$\left(-xy-xz-yz\right)\left(x+y+z\right)$

$\frac{dy}{dx}\left(\sqrt{1-y^2}\right)$

$\lim\:_{x\to\:+\infty}\:\left(\frac{x^3+3x^2+x^4+1}{x+x^5-3}\right)$

$81m^{16}-4n^{12}$

$\frac{\sin2\left(\frac{\pi}{6}\right)}{\sin\left(30\right)\tan\left(30\right)}$

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

$\left(\frac{-2}{11}a^{x+1}b^{x-3}c^2\right)\left(\frac{-44}{7}a^{x-3}b^2\right)$