Re: Question : How to force ( Exp[I x]/2+Exp[-I x]/2=cos(x) ) ?
- To: mathgroup at smc.vnet.net
- Subject: [mg3424] Re: Question : How to force ( Exp[I x]/2+Exp[-I x]/2=cos(x) ) ?
- From: Harald Berndt <haraldb at nature.berkeley.edu>
- Date: Wed, 6 Mar 1996 01:47:04 -0500
- Organization: University of California Forest Prodcts Lab
- Sender: owner-wri-mathgroup at wolfram.com
Yeou-Jyh Tsai wrote: > I use Mathematica's MatrixExp to generate the symbolic form of > a matrix's exponential. It gives me lots of > I x -I x -I x I x > E E I E IE > --- + ------ and -------- - ----- > 2 2 2 2 > which should be converted to Cos[x] and Sin[x], respectively. Does anyone > know how to do this ? Use ComplexExpand. Best, ==== [MESSAGE SEPARATOR] ====