$7a^2+3a^2-2a^2$

$\frac{1}{\sin\left(x\right)}-\sin\left(x\right)=\cos\left(x\right).$

$144x^6-2560y^{24}$

$cos\left(x\right)csc\left(x\right)+\left(-cos\left(x\right)cot\left(x\right)\right)sin\left(x\right)$

$24x-8y$

$\left(xy^3+9y^3\right)dy-7ydx\:=0$

$2x+x-x-2y$