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

$\frac{3}{8}\left(16x-24\right)$

$\int\left(2x+4\right)^5\:dx$

$\left(m-2n\right)\left(m^2+2mn+4n^2\right)$

$6b+\left[5b+7b\right]$

$\lim_{x\to1}\left(\frac{6x^2-36x}{x-6}\right)$

$lim\:_{t\to\:0}\left(\frac{1-cos\left(6t\right)}{2t}\right)$