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