$\frac{dr}{dt}=\frac{a}{s\left(t\right)}$

$\left|-4+-85\right|$

$\frac{x^3+3x^2+3x+1}{x}$

$21\cdot39$

$\frac{dy}{dx}\left(x^2y^2-4x=6\right)$

$\left(sin\left(x\right)\cdot\:sec\left(x\right)-sin\left(x\right)\right)^2+\left(1-\frac{1}{sec\left(x\right)}\right)^2$

$\frac{x}{2}+\frac{x+2}{3}=4$