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