$a\left(a-6\right)+6a$

$\frac{1}{x^2-1}-\frac{2}{x+1^2}$

$\frac{1-4x}{5}>\frac{2}{5}$

$\tan\left(287\right)-\frac{\sin\left(287\right)}{\cos\left(287\right)}$

$\frac{dy}{dx}=\frac{\left(7+x^4\right)}{\left(yx^2+y^4x^2\right)}$

$z^3-27$

$\frac{9}{25}a^2b^2+\frac{8}{5}a^2b+\frac{16}{9}a^2$