\[ x y'(x) \left (y(x) \sin \left (\frac {y(x)}{x}\right )-x \cos \left (\frac {y(x)}{x}\right )\right )-y(x) \left (y(x) \sin \left (\frac {y(x)}{x}\right )+x \cos \left (\frac {y(x)}{x}\right )\right )=0 \] ✓ Mathematica : cpu = 0.432297 (sec), leaf count = 31
\[\text {Solve}\left [-\log \left (\frac {y(x)}{x}\right )-\log \left (\cos \left (\frac {y(x)}{x}\right )\right )=2 \log (x)+c_1,y(x)\right ]\] ✓ Maple : cpu = 0.191 (sec), leaf count = 23
\[y \relax (x ) = \frac {c_{1}}{\cos \left (\RootOf \left (-\textit {\_Z} \cos \left (\textit {\_Z} \right ) x^{2}+c_{1}\right )\right ) x}\]