$\lim_{x\to0}\left(\frac{1}{ln\left(1+x\right)}-\frac{1}{\frac{1}{tan}2x}\right)$

$\frac{x^4+x+1}{\left(x-3\right)\left(x-18\right)\left(x-10\right)}$

$\left(2x-1\right)\left(x-5\right)>2x-13\:$

$c^2+2c+1$

$\sin\left(\frac{7\pi}{4}+x\right)-\cos\left(\frac{5\pi}{4}+x\right)$

$\sin\left(0.0099\right)$

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