$\frac{dy}{dx}=\frac{\left(xy+4y-x-4\right)}{\left(xy-9y+x-9\right)}$

$2x\cdot x+1\cdot x+2$

$csc^2x\:tan^2x-1=tan^2x$

$\frac{cos2x+sin2xcos2x}{cos^2x}$

$\lim_{x\to0}\left(\frac{-5\sin\left(6x^6\right)}{4x}\right)$

$\left(ab\right)^{m}\cdot\left(ab\right)^{m+1}\cdot\left(ab\right)^{m-1}$

$2589,07+108,329$