\[ y'(x)=\frac {\csc \left (\frac {y(x)}{2 x}\right ) \sec \left (\frac {y(x)}{2 x}\right ) \sec \left (\frac {y(x)}{x}\right ) \left (x^4 \sin \left (\frac {y(x)}{2 x}\right ) \sin \left (\frac {y(x)}{x}\right ) \cos \left (\frac {y(x)}{2 x}\right )+x^3 \sin \left (\frac {y(x)}{2 x}\right ) \sin \left (\frac {y(x)}{x}\right ) \cos \left (\frac {y(x)}{2 x}\right )-\frac {1}{2} y(x) \sin \left (\frac {y(x)}{x}\right )+x \sin \left (\frac {y(x)}{2 x}\right ) \sin \left (\frac {y(x)}{x}\right ) \cos \left (\frac {y(x)}{2 x}\right )+\frac {1}{2} y(x) \sin \left (\frac {y(x)}{2 x}\right ) \cos \left (\frac {y(x)}{2 x}\right )+\frac {1}{2} y(x) \sin \left (\frac {3 y(x)}{2 x}\right ) \cos \left (\frac {y(x)}{2 x}\right )\right )}{x} \] ✓ Mathematica : cpu = 0.0598215 (sec), leaf count = 29
\[\left \{\left \{y(x)\to x \sin ^{-1}\left (x e^{c_1+\frac {x^3}{3}+\frac {x^2}{2}}\right )\right \}\right \}\]
✓ Maple : cpu = 0.126 (sec), leaf count = 25
\[ \left \{ y \left ( x \right ) ={\frac {x}{2}\arccos \left ( {{\rm e}^{{\frac {2\,{x}^{3}}{3}}}}{{\rm e}^{{x}^{2}}}{\it \_C1}\,{x}^{2}+1 \right ) } \right \} \]