\[
\boxed{
{\frac {\rm d}{{\rm d}x}}y \left( x \right) ={\frac { \left( y \left( x \right)  \right) ^{2} \left( -2\,y \left( x \right) +2\,{x}^{2}+2\,{x}^{2}y \left( x \right) +y \left( x \right) {x}^{4} \right) }{{x}^{3} \left( {x}^{2}-y \left( x \right) +{x}^{2}y \left( x \right)  \right) }}=0}
\]