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