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

$\lim\:_{x\to\:0}\left(\frac{e^x\cdot\:\sin\:\left(x\right)-x}{2x^2+x}\right)$

$\frac{x^{3a+6}}{x^{a-6}}$

$\left(x^3e^{2x^2+3y^2}dx\right)-y^3e^{-x^2-2y^2}dy$

$\left(3a+4b\right)\:.\:\left(2a-b\right)$

$\frac{dy}{dx}=\frac{y^2+xy-4x^2}{x^2}$

$12x^2+11x+2$