Re: Complex numbers
- To: mathgroup at smc.vnet.net
- Subject: [mg37141] Re: [mg37138] Complex numbers
- From: Andrzej Kozlowski <andrzej at platon.c.u-tokyo.ac.jp>
- Date: Sun, 13 Oct 2002 05:56:21 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
To start with, what you are saying is simply not true. A simple example:
In[1]:=
Abs[(z1 - z2)/(1 - z1*Conjugate[z2])] /.
{z1 -> 1 + I, z2 -> 1 - I}
Out[1]=
2/Sqrt[5]
Presumably you meant Abs[(z1 - z2)/(z1 - Conjugate[z2]) in which case:
In[1]:=
ComplexExpand[Abs[(z1-z2)/(z1- Conjugate[z2])],TargetFunctions->{Im,Re}]
Out[1]=
1
Andrzej Kozlowski
Yokohama, Japan
http://www.mimuw.edu.pl/~akoz/
http://platon.c.u-tokyo.ac.jp/andrzej/
On Saturday, October 12, 2002, at 06:05 PM, CeZaR wrote:
> Hi,
>
> I want to perform this calculation:
>
> In[1]:=z1 = a1 + b1 I
> Out[1]=a1 + \[ImaginaryI] b1
> In[3]:=z2 = a2 + b2 I
> Out[3]=a2 + \[ImaginaryI] b2
> In[19]:=Abs[(z1 - z2)/(1 - z1 Conjugate[z2])]
>
> This should output 1! But it doesn't work...
>
> Also, Abs[a1+b1 I] doesn't get the right result.
> Any ideeas?
>
> Thanks,
> CeZaR
>
>
>