O17-C029 > restart: > ed1:=diff(y(x),x$2)+exp(I*x)*diff(y(x),x)+y(x)=0; / 2 \ |d | /d \ ed1 := |--- y(x)| + exp(x I) |-- y(x)| + y(x) = 0 | 2 | \dx / \dx / > ed2:=diff(y(x),x$2)+exp(I*x)*diff(y(x),x)+y(x)=exp(-I*x); / 2 \ |d | /d \ ed2 := |--- y(x)| + exp(x I) |-- y(x)| + y(x) = exp(-I x) | 2 | \dx / \dx / > s1:=dsolve(ed1,y(x)); s1 := y(x) = _C1 (1 - exp(-I x) I) + _C2 exp((-x + exp(x I)) I) > dsolve(ed2,y(x)); y(x) = (1 - exp(-I x) I) _C2 + exp((-x + exp(x I)) I) _C1 - 1/2 Ei(1, exp(x I) I) exp((-x + exp(x I)) I) > varcons:=subs(s1,_C1=a,_C2=b,y(x)); varcons := a (1 - exp(-I x) I) + b exp((-x + exp(x I)) I) > varcons2:=diff(varcons,x)=exp(-I*x); varcons2 := -a exp(-I x) + b (-1 + exp(x I) I) exp((-x + exp(x I)) I) I = exp(-I x) > resol:=solve({varcons,varcons2},{a,b}); exp(-I x) resol := {a = - ------------------------------------, b = - -I - exp(x I) + exp(x I) exp(-I x) I (-1 + exp(-I x) I) exp(-I x)/(exp((-x + exp(x I)) I) (-I - exp(x I) + exp(x I) exp(-I x) I))} > cprim1:=unapply(subs(resol,a),x);cprim2:=unapply(subs(resol,b),x); exp(-I x) cprim1 := x -> - ------------------------------------ -I - exp(x I) + exp(x I) exp(-I x) I cprim2 := x -> - (-1 + exp(-I x) I) exp(-I x)/( exp((-x + exp(x I)) I) (-I - exp(x I) + exp(x I) exp(-I x) I) ) > c1:=int(cprim1,0..x); c1 := -1/2 I (exp(2 I x) - 1) exp(-2 I x) > c2:=int(cprim2,0..x); Warning, unable to determine if 1/2*Pi+Pi*_Z1 is between 0 and x; try to use assumptions or set _EnvAllSolutions to true x / | c2 := | - (-1 + exp(-I _X) I) exp(-I _X)/( | / 0 exp((-_X + exp(_X I)) I) (-I - exp(_X I) + exp(_X I) exp(-I _X) I)) d_X >