Determine the general solution of the exact differential equation

1−$\displaystyle \frac{x}{x^2+y^2}$-($\displaystyle \frac{y}{x^2+y^2}$)$\displaystyle \frac{dy}{dx}$=0

Fix the constant of integration according to the initial condition y(0) = e and write down the explicit form of the solution.

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