\[
\boxed{
2\,x{\frac {{\rm d}^{3}}{{\rm d}{x}^{3}}}y \left( x \right) +3\, \left( 2\,ax+k \right) {\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left( x \right) +6\, \left( ak+bx \right) {\frac {\rm d}{{\rm d}x}}y \left( x \right) + \left( 3\,bk+2\,cx \right) y \left( x \right) =0}
\]