Solution of the differential equation \(\left\{ \frac 1x - \frac{y^2}{(x-y)^2}\right\}dx + \left\{\frac{x^2}{(x-y)^2} - \frac 1y\right\}dy = 0\) is
a. \(log_e\frac xy + \frac{xy}{x-y} = C\)
b. \( \frac{xy}{x-y} = C.e^{x/y}\)
c. \(log_e\frac xy =C+ \frac{xy}{x-y} \)
d. None of these