\[ y'(x)=\frac {\sin \left (\frac {y(x)}{x}\right ) \csc \left (\frac {y(x)}{2 x}\right ) \sec \left (\frac {y(x)}{2 x}\right ) \left (2 x^3 \sin \left (\frac {y(x)}{2 x}\right ) \cos \left (\frac {y(x)}{2 x}\right )+y(x)\right )}{2 x} \] ✓ Mathematica : cpu = 0.123113 (sec), leaf count = 23
\[\left \{\left \{y(x)\to 2 x \cot ^{-1}\left (e^{-\frac {x^2}{2}-c_1}\right )\right \}\right \}\] ✓ Maple : cpu = 0.177 (sec), leaf count = 64
\[\left \{y \left (x \right ) = x \arctan \left (\frac {2 c_{1} {\mathrm e}^{\frac {x^{2}}{2}}}{c_{1}^{2} {\mathrm e}^{x^{2}}+1}, \frac {-c_{1}^{2} {\mathrm e}^{x^{2}}+1}{c_{1}^{2} {\mathrm e}^{x^{2}}+1}\right )\right \}\]