$\frac{dy}{dx}=-2x\:+2$

$\frac{senx}{tanx}+tanx$

$\lim_{x\to0}\left(\frac{sin\left(x^3\right)}{x^2}\right)$

$\left(2x-3y+1\right)\left(2x-3y+1\right)$

$\left(\frac{2}{3}x^{-2}-\frac{1}{2}y\right)^3$

$\left(1-\sin\left(90-x\right)\right)\left(1+\sin\left(90-x\right)\right)$

$\frac{7x}{x+3}+\frac{5x}{x+3}$