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