\[ y'(x)=\frac {\sin \left (\frac {y(x)}{x}\right ) \csc \left (\frac {y(x)}{2 x}\right ) \sec \left (\frac {y(x)}{2 x}\right ) \left (2 x^2 \sin \left (\frac {y(x)}{2 x}\right ) \cos \left (\frac {y(x)}{2 x}\right )+y(x)\right )}{2 x} \] ✓ Mathematica : cpu = 0.0689802 (sec), leaf count = 19
\[\left \{\left \{y(x)\to 2 x \cot ^{-1}\left (e^{-c_1-x}\right )\right \}\right \}\]
✓ Maple : cpu = 0.09 (sec), leaf count = 48
\[ \left \{ y \left ( x \right ) =\arctan \left ( 2\,{\frac {{{\rm e}^{x}}{\it \_C1}}{{{\it \_C1}}^{2} \left ( {{\rm e}^{x}} \right ) ^{2}+1}},{\frac {-{{\it \_C1}}^{2} \left ( {{\rm e}^{x}} \right ) ^{2}+1}{{{\it \_C1}}^{2} \left ( {{\rm e}^{x}} \right ) ^{2}+1}} \right ) x \right \} \]