Re: Is this a bug?

*To*: mathgroup at smc.vnet.net*Subject*: [mg90842] Re: Is this a bug?*From*: Peter Breitfeld <phbrf at t-online.de>*Date*: Sat, 26 Jul 2008 04:20:16 -0400 (EDT)*References*: <g6c982$brv$1@smc.vnet.net>

mailcwc at gmail.com schrieb: > I tried to solve the following equation with mathematica 6.03 > > Solve[{Abs[X+Y I]==5,X==3},{X,Y}] > > and got the answer > > {{X -> 3, Y -> -2 I}, {X -> 3, Y -> 8 I}} > > Am I suppose to get {{X -> 3, Y -> 4 I}, {X -> 3, Y -> -4 I}} ? No, you suppose to get {{X->3, Y->4},{X->3, Y->-4}} (without I), that's what I would expect too. The solutions Mathematica gives are correct -- just plug in. But you are right, they are not what one would expect. This will give you the expected result: Solve[{ComplexExpand[Abs[x+I y]]==5,x==3},{x,y}] Gruss Peter -- ==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-== Peter Breitfeld, Bad Saulgau, Germany -- http://www.pBreitfeld.de