$\frac{dy}{dx}\left(\frac{1+2y^2}{y\sin\:\left(x\right)}\right)$

$\frac{\csc^2\left(x\right)-2}{\csc^2\left(x\right)}$

$6x^2+7x-20$

$- 3.28 + 3$

$\left(u-3v\right)+\left(-5u-4\cdot v\right)+\left(u-3\right)$

$\left(-9x\:+\:6\right)\:\left(-9x\:-\:6\right)$

$220+45-6+20$