$\lim_{x\to\infty}\:\frac{1}{2-1^x}$

$\frac{dy}{dx}+\frac{y}{x\cdot ln\left(x\right)}=\frac{9e^x}{ln\left(x\right)}$

$\frac{d}{dx}\ln\left(\frac{\sqrt{x}}{2^xtan^5x}\right)$

$\left(x-1\right)x\left(2x-3\right)$

$sinx\:+\:cosx\:=\:1.2$

$5x^2+10x^2-25x$

$\lim_{x\to\infty}\left(\frac{2x^2+3x+1}{4x+3}\right)$