\[
\boxed{
{\frac { \left( 1-\mbox {D} \left( j \right)  \left( y \left( x \right)  \right)  \right)  \left( {\frac {\rm d}{{\rm d}x}}y \left( x \right)  \right) ^{2}}{j \left( y \left( x \right)  \right) }}+f \left( x \right) {\frac {\rm d}{{\rm d}x}}y \left( x \right) +{\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left( x \right) +g \left( x \right) j \left( y \left( x \right)  \right) =0}
\]