$2x-3x+x$

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

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

$\lim\:_{x\to\:\infty\:}\left(\frac{e^{\frac{x}{10}}}{x^3}\right)$

$\left(-1\right)^3-\left(-3\right)^2\left(-2\right)-1\left(1-2\right)^3+3-2\left(-1\right)+4+3\left(-2\right)-\left(2\right)\left(-1\right)$

$x^2-196$

$y'+ycosx=4cosx,y\left(0\right)=6$