$\frac{3-\sqrt{4^2-7}}{4-4}$

$\left(3x-6\right)\left(2x-6\right)$

$\lim_{x\to\frac{\pi}{2}}\left(\frac{\left(cos\left(x\right)sin\left(x\right)\right)}{5cos\left(3x\right)}\right)$

$\frac{-4x^5+x^3+2x^2-3+1}{x+1}$

$a3:a$

$3x^4+2y^2=x^3$

$\left(a^2b^4+8c\right)\left(a^2b^4-10c\right)$