$\frac{dy}{dx}=1-x$

$\lim_{x\to1}\left(\frac{3x^3-7x^2+5x-1}{x^3-x^2-3x+1}\right)$

$\frac{2}{9}x=12$

$\lim_{x\to0}\left(\frac{1-\cos\left(x\right)}{2xcosx}\right)$

$\left(34\right)+\left(26\right)+\left(15\right)$

$\int_{-\infty}^{-2}\left(\frac{\ln\left(x\right)}{x}\right)dx$

$\frac{dy}{dt}+4y=e^t$