$\left(2\cdot x-2\sqrt{x^2-x+3}\right)\cdot\left(2\cdot\:x+2\sqrt{x^2-x+3}\right)$

$\lim_{x\to0}\left(\frac{9-4y^2}{9y^2+4y}\right)$

$\frac{dy}{dx}\:+\frac{2y}{300+x}=6\:$

$x-\frac{x^3}{4}+\frac{x^5}{9}-\frac{x^7}{16}$

$16:\:\left(-\:2\right)\:-\:\left(-\:4\:+\:2\right)\:+\:5.\:\left(-\:1\right)\:$

$\frac{dy}{dx}=\frac{y\left(y-1\right)}{\left(y+1\right)}$

$x\le3x+2$