$nx-mx$

$\left(\frac{x}{2}+\frac{y}{3}\right)^4$

$\int e^{-y}\cdot\cos\left(2yx\right)dy$

$\left(2x-y+5\right)^2$

$\lim_{x\to7}\left(\frac{x-7}{3x^2-21}\right)$

$\lim_{x\to2}\left(\frac{sen\left(\sqrt{x}-\sqrt{2}\right)}{\left(x-2\right)\left(x^3+1\right)}\right)$

$\int\:\frac{3x+6}{\sqrt{2x^2+8x+3}}dx$