$\frac{5}{6}\left(x^2\right)-\frac{2}{3}\left(y^2\right)+\frac{3}{4}\left(xy\right)-\frac{1}{2}\left(xy\right)-\frac{1}{6}\left(x^2\right)+\frac{1}{8}\left(y^2\right)\frac{5}{6}\left(xy\right)-\frac{1}{3}\left(x^2\right)+\frac{1}{4}\left(y^2\right)$

$\left(2-x^4\right)\left(3-x^8\right)$

$50x-10ax+50y-10ay$

$-7\left(10\right)$

$\frac{\sin\left(-t\right)}{1+\cos\left(-t\right)}-\csc\left(-t\right)$

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

$\frac{5x^{2}+3x-1}{\left(1+x^{2}\right)\left(x-2\right)}$