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