\[
\boxed{
{\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left( x \right) - \left( 2\,{{\rm e}^{x}}+1 \right) {\frac {\rm d}{{\rm d}x}}y \left( x \right) +{{\rm e}^{2\,x}}y \left( x \right) -{{\rm e}^{3\,x}}=0}
\]