$\frac{d}{dx}9\arctan\left(x-\sqrt{1+x^2}\right)$

$\frac{\left\{10-\left(2-8\right)^2\right\}}{\left(3^2+2^2\right)}$

$4m^2n^2\cdot3mn$

$49x^2+14x+4$

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

$e^{-2y}dy=e^{3y}dx$

$\int\frac{x^4}{\left(x^2-x+1\right)\left(x^2+1\right)^2}dx$