$\lim_{x\to\infty}\left(x+5\right)^{e^{-5x}}$

$\lim_{x\to4.999}\left(x+9\right)$

$\frac{\left(-2\right)^3\left(16\right)^{-3}\left(3^3\right)^3}{\left(-4\right)^4\left(54\right)^{-2}}$

$2\left(\frac{2}{3}x+\frac{xy}{4}\right)^2$

$-\sqrt{-\frac{1}{4}}$

$\left(\frac{3}{4}t+\frac{1}{5}q\right)\left(\frac{3}{4}t-\frac{1}{5}q\right)$

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