||'''Book'''|| Advanced Engineering Mathematics ||
 ||'''Author'''|| Erwin Kreyszig ||
 ||'''Edition'''|| 8th Edition ||

/* code_begins */

{{{
#2.4-3
x=var('x')
y=function('y',x)
y=x*e^(-x)
de=diff(y,x,2)-diff(y,x,1)-2*y
print de

}}}

/* code_ends */

 * '''Solution by''': 
   *K B PATIL,LECTURER,SIGCOE KOPERKHAIRANE NAVI MUMBAI.