Re: Getting Symbolic Real and Imag Parts? (Once Again)
- To: mathgroup at smc.vnet.net
- Subject: [mg33495] Re: [mg33443] Getting Symbolic Real and Imag Parts? (Once Again)
- From: Andrzej Kozlowski <andrzej at tuins.ac.jp>
- Date: Sun, 24 Mar 2002 01:43:46 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
How about simply:
In[3]:=
ComplexExpand[Re[Sin[a+I b]]]
Out[3]=
Cosh[b] Sin[a]
In[4]:=
ComplexExpand[Im[Sin[a+I b]]]
Out[4]=
Cos[a] Sinh[b]
??
On Thursday, March 21, 2002, at 02:27 PM, aes wrote:
> OK, so you can use ComplexExpand expand to find the symbolic real and
> imag
> parts of an expression -- e.g. the input
>
> zComplex = ComplexExpand[ Sin[a+I b], TargetFunctions->{Re,Im}]
>
> gives as output
>
> Cosh[b] Sin[a] + I Cos[a] Sinh[b]
>
> as desired. But now, how do I get Mathematica to peel out the
> symbolically real and
> imaginary parts of this? -- that is, what inputs
>
> zR = ???
>
> zI = ???
>
> will give as outputs
>
> Cosh[b] Sin[a]
>
> and
>
> Cos[a] Sinh[b]
>
> (Maybe an example in the ComplexExpand Help file would be helpful?)
>
>
>
Andrzej Kozlowski
Toyama International University
JAPAN
http://platon.c.u-tokyo.ac.jp/andrzej/