The solution of the differential equation $ \large\frac{dy}{dx} =\frac{xy}{x^2+y^2}$ is

Question

$\begin{array}{1 1} ay^2=e^{x^2/y^2} \\ ay=ex^{x/y} \\ y=e^{x^2} +e^{y^2}+c \\ y= e^{x^2}+y^{2}+c \end{array} $