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

$-2\left(2\right)^2\left(3\right)^6+16\left(2\right)^2\left(3\right)^6$

$\frac{d}{dx}y=x^2+3x^5+4$

$\lim_{x\to0}\left(\frac{x^2}{\cos^2\left(x\right)}\right)$

$\int\left(\frac{e^{3\sqrt{x}}}{\sqrt{x}}\right)dx$

$\int\frac{w^3+1}{w\left(w-1\right)^3}dx$

$\cos\left(120\right)=\frac{-6+6x}{\sqrt{45}\left(\sqrt{4+x^2}\right)}$