wffc:=diff(y(x),x$2)+2*diff(y(x),x)+y(x)=0:
tongjie:=dsolve(wffc,y(x)):tejie:=dsolve({wffc,y(0)=4,D(y)(0)=-2},y(x)):
tongjiequxian:=[seq(seq(rhs(tongjie),_C1=3..5),_C2=0..4)]:
p1:=plot(tongjiequxian,x=-2..2,y=0..8,thickness=1,color=red):
p2:=plot(rhs(tejie),x=-2..2,y=0..8,thickness=5,color=blue):
display(p1,p2,scaling=constrained);
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