$\frac{3a^{2}+9a-6}{3a}$

$\:\left(\:x-6\right)\left(x+5\right)=\:$

$7-\left(13+9\right)$

$63.45+42.30$

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

$3\left(6x+1\right)$

$\lim_{x\to2\pi}\left(\frac{\cos\left(x\right)-1}{x-2\pi}\right)$