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Re: Real and Imaginary Parts of complex functions
Posted:
Feb 27, 2013 3:04 AM


Just use ComplexExpand with assumes that all variables are Reals unless otherwise specified.
Re[x + y*I] // ComplexExpand
x
Re[1/(x + y*I)] // ComplexExpand
x/(x^2 + y^2)
Bob Hanlon
On Tue, Feb 26, 2013 at 1:09 AM, Brentt <brenttnewman@gmail.com> wrote: > > Hello, > > 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? > >



