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

$\frac{\cos\left(x\right)+2\tan\left(x\right)-\sec\left(x\right)}{2-\sin\left(x\right)}=\tan\left(x\right)$

$-1000\cdot200$

$\left(x+7y\right)\left(x-3y\right)$

$\frac{dy}{dx}=\left(4x-9\right)^2$

$2a-7a-3a+7b-10a+9\:b$

$-3-7\cdot\left(-3^2\right)$