$245+-680+135+-791+456+462+231+-564+680$

$52\:-x\:>0$

$\frac{dy}{dx}=-y\frac{\sin\left(x\right)}{\cos\left(x\right)}$

$2\cdot26$

$\sin\left(x\right)\left(\frac{1}{\sin\left(x\right)}\right)-\sin^2\left(x\right)=\cos^2\left(x\right)$

$\int\left(x^2\sqrt{9-4x}\right)dx$

$2x\frac{dy}{dx}=1+y^2$