$\lim_{x\to\infty}\left(\frac{2000}{1+1999\cdot e^{-0.8905\cdot x}}\right)$

$\frac{dy}{dx}=\frac{5}{5x-1}-\frac{1}{x+1}$

$467.33+3562.2$

$\frac{d}{dx}-\frac{x^2}{y^2}$

$\frac{\left(0.2313\right)-\left(2\cdot0.0045\right)+\left(0.057\right)}{\left(2\cdot0.0625\right)^2}$

$\frac{a^7.a^{-2}}{a^4}$