$\lim_{x\to-\infty}\left(3xe^{\frac{x}{3}}\right)$

$\frac{d}{dx}\left(0.7y^2y'\right)$

$2x^2\cdot4$

$\int\left(\frac{2x^2-x+2}{x^5-8x^3}\right)dx$

$x^2-3x+5=0$

$\lim_{m\to0}\left(\frac{\left(cos\left(x+m\right)-cos\left(x\right)\right)}{m}\right)$

$\frac{dy}{dx}-9y=9xe^{-3x}$