$2y'=y$

$2\:-2^2\:\:-1\:3-\left[3-2\:3\:-\:\left(5-1\:3\:-\:3-1\:3\right)\:+\:2\:-4-12\:\right]$

$-27-45-32-28$

$c^2+2cd+d^2$

$\frac{1-\sin^2\left(a\right)}{\cos\left(a\right)}=\sin\cdot\cos^2\left(a\right)$

$\lim_{x\to-2}\left(\frac{x-2}{\sqrt{x}-2}\right)$

$\frac{\left(2\right)}{3x+6}$