$\frac{dy}{dx}+\left(\frac{1}{x}-1\right)y=1$

$\lim_{z\to0}\:\frac{x^2-2x}{x}$

$\lim_{x\to0}\left(\frac{\left(1+x\right)\left(1-x\right)}{x^6}\right)$

$\lim_{x\to1}\left(\frac{\ln\left(x\right)}{\left(x-1\right)^3}\right)$

$x^{2}+3x+2>0$

$\left(-5x^2\right)\cdot\left(4x^4\right)+2x^3\cdot\left(-5x\right)\cdot\left(x^3\right)$

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