\[
\boxed{
{\frac {\rm d}{{\rm d}x}}y \left( x \right) =1/3\,{\frac {x \left( y \left( x \right)  \right) ^{3}{{\rm e}^{3\,{x}^{2}}}}{ \left( 3\,{{\rm e}^{3/2\,{x}^{2}}}+{{\rm e}^{3/2\,{x}^{2}}}y \left( x \right) +3\,y \left( x \right)  \right) {{\rm e}^{9/2\,{x}^{2}}}}}=0}
\]