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

$5x^8-\:10x^7\:+\:10x^6$

$2\cos\left(x\right)\sin\left(x\right)=\sin2\left(x\right)$

$\left[5\left(5x\right)+4y\right]\left[5\left(5x\right)-4y\right]$

$\sin\left(x\right)+\sin\left(x\right)\cos\left(x\right)^2$

$-2\cot\left(\frac{\pi}{6}\right)+\frac{\pi}{6}-3\tan\left(\frac{\pi}{6}\right)$

$\frac{\left(x-1\right)}{x^2-4}+\frac{1}{x-2}=\frac{\left(x+4\right)}{x+2}$