Re: Absolute value
- To: mathgroup at smc.vnet.net
- Subject: [mg110608] Re: Absolute value
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Mon, 28 Jun 2010 02:28:13 -0400 (EDT)
Presumably, you meant the square of your expression
expr = Abs[Exp[I*phi1] + Exp[I*phi2]]^2;
ComplexExpand[expr,
TargetFunctions -> {Re, Im}] //
FullSimplify
2 (cos(phi1-phi2)+1)
Bob Hanlon
---- Marco Masi <marco.masi at ymail.com> wrote:
=============
I would like to calculate the absolute value of complex quantities. For example Abs[Exp[I phi1]+Exp[I*phi2]], which sould give 2 (1+cos(phi1-phi2)). However it does not work. I tried to use real numbers as assumtion, but it always answers "Abs[Exp[I phi1]+Exp[I*phi2]]". What am I doing wrong?
Regards, Mark.