$\left(1-4\cdot9\right)$

$\frac{d}{dx}4xe^{3x}$

$\frac{dy}{dx}+\frac{y}{x}=8\:\sin\left(x\right)$

$\lim_{x\to0}\left(\frac{\sin\left(7x\right)^2\cos\left(9x\right)}{\tan\left(3x\right)\sin\left(4x\right)}\right)$

$\int2x^6dx$

$\frac{d^2}{dx^2}\left(x^3+y^3=27\right)$

$y^2-21y-22$