How do I solve the differential equation [math]\frac{dy}{dx}=\frac{y-3}{y^2+x^2}[/math]? What is the solution of differential equation [math]\frac{dy}{dx}= \frac{y^2+x^2+2xy+y+x} {y^2+x^2+2xy+2y+2x}?[/math]