$9cos\left(2x\right)=3$

$\left(x+y-z\right)-\left(-x-y+z\right)$

$\frac{\left(2x+y\right)-\left(2x-y\right)^2}{8xy}$

$\int\frac{2\left(2x-5\right)}{x^2-5x+8}dx$

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

$\left(x^4-3\right)\left(x^4-8\right)$

$\int\frac{2x^2-3x-4}{x\left(x^2+2x+2\right)}dx$