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wrong definite integral for %e^(-2*%i*%pi*t)*(%e^(2*%i*%pi*t)+1) #3328

Open rtoy opened 1 month ago

rtoy commented 1 month ago

Imported from SourceForge on 2024-07-07 20:53:48 Created by sosan on 2019-03-31 20:19:56 Original: https://sourceforge.net/p/maxima/bugs/3545


maxima 5.42.2 Lisp: SBCL 1.4.10.debian

simple function gives right answer (see u1,u2) but rewriting u1 into v1 gives wrong result for definite integral, indefinite is right

(%i27)  u1: %e^(-2*%i*%pi*t)+1;
(u1)    %e^(-2*%i*%pi*t)+1
(%i36)  u2: ratsimp(integrate(u1,t,-1/6,1/6));
(u2)    (2*%pi+3^(3/2))/(6*%pi)                         OK
(%i37)  v1: %e^(-2*%i*%pi*t)*(%e^(2*%i*%pi*t)+1);
(v1)    %e^(-2*%i*%pi*t)*(%e^(2*%i*%pi*t)+1)
(%i38)  ratsimp(integrate(v1,t,-1/6,1/6));
(%o38)  sqrt(3)/(2*%pi)                                    BAD
rtoy commented 1 month ago

Imported from SourceForge on 2024-07-07 20:53:49 Created by robert_dodier on 2019-04-02 17:11:12 Original: https://sourceforge.net/p/maxima/bugs/3545/#9db8


Diff:


--- old
+++ new
@@ -2,6 +2,7 @@

 simple function gives right answer (see u1,u2)
 but rewriting u1 into v1 gives wrong result for definite integral, indefinite is right
+~~~~
 (%i27) u1: %e^(-2*%i*%pi*t)+1;
 (u1)   %e^(-2*%i*%pi*t)+1
 (%i36) u2: ratsimp(integrate(u1,t,-1/6,1/6));
@@ -10,3 +11,4 @@
 (v1)   %e^(-2*%i*%pi*t)*(%e^(2*%i*%pi*t)+1)
 (%i38) ratsimp(integrate(v1,t,-1/6,1/6));
 (%o38) sqrt(3)/(2*%pi)                                    BAD
+~~~~