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