$\frac{dy}{dx}=\frac{y^3}{\left(x+4\right)}$

$\lim_{x\to0}\left(\frac{x}{\sqrt{x+9}-3}\right)$

$\frac{6y}{\left(1+y^2\right)}dy=\left(1+x^2\right)dx$

$\int4\cos\left(4x\right)e^xdx$

$6\cdot\left(-1\right)\cdot\left(-2\right)\:\cdot50\cdot\left(-1\right)$

$\frac{x+2}{x^2+6x+8}$

$\lim_{x\to2}\left(\frac{x^2-3x+1}{x^2-4x+5}\right)$