$2\cos^2\left(x\right)-\cos\left(x\right)=0$

$\left(y+7\right)\left(y-3\right)$

$\lim_{x\to0}\left(\frac{\ln\left(x+1\right)+5\cdot\sin\left(3x\right)+\sin\left(2x\right)}{x^2}\right)$

$3x-\frac{4a}{2b^3}$

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

$\int_3^{\infty}\left(\frac{1}{1\sqrt{16+x^2}}\right)dx$

$\frac{x-1}{x-1}$