Re: Circle equation problem

*To*: mathgroup at smc.vnet.net*Subject*: [mg61580] Re: Circle equation problem*From*: Daniele Lupo <danwolf80_no_spam_ at libero.it>*Date*: Sat, 22 Oct 2005 05:11:26 -0400 (EDT)*References*: <dja2c3$fig$1@smc.vnet.net> <djcg72$6ci$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Il Sat, 22 Oct 2005 04:46:26 +0000 (UTC), Jens-Peer Kuska ha scritto: > expr = Abs[p]^2 == Abs[(G - X + I*Y)/(-1 + G*(X + > I*Y))]^2; > > expr1 = ComplexExpand[expr, TargetFunctions -> > {Re, Im}] // FullSimplify; > > expr2 = (Expand /@ (expr1 /. a_ == b_/c_ :> a*c == > b)) /. > a_ == b_ :> a - b == 0 > > and you see that at least X must be scaled by > x->X/(p*G) > Hi. It does not work. As I've said, G and p are complex parameters, so I must to write, for expr1 expr1 = ComplexExpand[expr, {p, G}, TargetFunctions -> { Re, Im}] // FullSimplify Then, using your command for expr2, I see X and Y that are present in the denominator, so the problem it's not resolved... Daniele Lupo