RE : problem with integrate and differentiate a function with trigonometric terms
Subject: RE : problem with integrate and differentiate a function with trigonometric terms
From: Leo Butler
Date: Fri, 17 Jul 2009 21:13:26 +0100 (BST)
On Fri, 17 Jul 2009, laurent couraud wrote:
< factor(trigsimp(trigexpand(trigrat(diff(integrate((E*sin(E)-e*sin(E)*sin(E))/(1-e*cos(E))^2,E),
< E)))));
I think that one only needs to use 'trigrat' to get the desired
simplification:
(%i2) expr : (E*sin(E)-e*sin(E)*sin(E))/(1-e*cos(E))^2$
(%i3) I : integrate(expr,E)$
(%i4) expr2 : diff(I,E)$
(%i5) trigrat(expr-expr2);
(%o5) 0
Leo
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