\[
\boxed{
{\frac {\rm d}{{\rm d}x}}y \left( x \right) =-F \left( x \right)  \left( - \left( y \left( x \right)  \right) ^{2}+2\,{x}^{2}y \left( x \right) +1-{x}^{4} \right) +2\,x=0}
\]