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