$\frac{d^2}{dx^2}\left(3x^2+1\right)$

$\frac{dy}{dx}=-\frac{\left(x-y\cdot\:\:cos\left(\frac{y}{x}\right)\right)}{\left(xcos\left(\frac{y}{x}\right)\right)}$

$248h^5a^3+341g^3h^3-155h\:$

$\int\left(\frac{2x}{5x^2+1}\right)dx$

$\frac{dy}{dx}-7y=e^x$

$\left(\frac{3}{4}xyz^2\right)\left(\frac{4}{5}xyz\right)$

$-54+2$