Re: How Expand?
- To: mathgroup at smc.vnet.net
- Subject: [mg127834] Re: How Expand?
- From: daniel.lichtblau0 at gmail.com
- Date: Sat, 25 Aug 2012 04:27:01 -0400 (EDT)
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On Friday, August 24, 2012 4:08:07 AM UTC-5, news wrote: > Hi folks, > > > > How can I expand the following : > > > > [ 1 + cos(x) + i sin(x) ]^3 > > > > to obtain; > > > > 8 cos(x/2)^3 [cos(3x/2)+ i sin(3x/2)] > > > > Thanks a lot. > > > > Max. This will come pretty close. In[6]:= ee = 1+Cos[x]+I*Sin[x]; In[7]:= InputForm[TrigFactor[TrigExpand[ee]]] Out[7]//InputForm= Cos[x/2]*(2*Cos[x/2] + (2*I)*Sin[x/2]) Daniel Lichtblau Wolfram Research