Re: Real and Imaginary Parts of complex functions
- To: mathgroup at smc.vnet.net
- Subject: [mg129936] Re: Real and Imaginary Parts of complex functions
- From: Bill Rowe <readnews at sbcglobal.net>
- Date: Wed, 27 Feb 2013 03:05:17 -0500 (EST)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- Delivered-to: l-mathgroup@wolfram.com
- Delivered-to: mathgroup-newout@smc.vnet.net
- Delivered-to: mathgroup-newsend@smc.vnet.net
On 2/26/13 at 1:09 AM, brenttnewman at gmail.com (Brentt) wrote:
>I was wondering why this works
>IN[]:= Refine[Re[x + y I], Element[x , Reals] && Element[y , Reals]]
>Out[]:= x
>But this does not
>In[]:= Refine[Re[1/(x + y I)], Element[x , Reals] && Element[y ,
>Reals]]
>Out[]:= Re[1/(x + y I)]
>Is there a nice built in way to get the real and imaginary parts of
>a complex function?
ComplexExpand, for example:
In[3]:= List @@ ComplexExpand[1/(x + y I)]
Out[3]= {x/(x^2 + y^2), -((I*y)/(x^2 + y^2))}