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

$-56+4$

$\lim_{x\to1}\left(\frac{\ln\left(2x^2\right)}{\tan\left(x-1\right)}\right)$

$-7-17.68$

$\left(\sqrt{3}+3\right)\left(\sqrt{x}-3\right)$

$\frac{-45x-2x+x^3}{x+7}$

$\frac{\left(4xy^2\right)^2}{\left(2x^2y^{-1}\right)^{-3}}$