$\left(cotx+cscx\right)\cdot\left(tanx-sinx\right)$

$\left(d+5g-v-3\right)\left(5-3v+4g+7d\right)$

$\left(x+1\right)\left(x+2\right)\left(x+3\right)\left(x+4\right)-2x\left(x+5\right)$

$\left(8\right)\left(-23\right)$

$\int_0^{\frac{\pi}{2}}\left(\sqrt{16-x^2}\right)dx$

$-2\left(8-2r\right)+3r$

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