Re: Series[] command
- To: mathgroup at smc.vnet.net
- Subject: [mg55952] Re: Series[] command
- From: dh <dh at metrohm.ch>
- Date: Tue, 12 Apr 2005 05:26:01 -0400 (EDT)
- References: <d3cq8l$6er$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Hello Kris, The equivalence of two expressions is in general a non-solvable problem, but in your case you can convince yourself that the two expression are equivalent by: ma*mb + ma(b-mb) + mb(a-ma) + (a-ma)(b-mb) == b(a-ma) + ma(b-mb) + ma*mb //simplify what gives True. Sincerely, Daniel Kris Preacher wrote: > Hi all, > > I need to obtain the second-order Taylor series expansion of a*b around the > points ma and mb. I thought Mathematica's Series[] command would do the > trick, but no. The correct answer is: > > ma*mb + ma(b-mb) + mb(a-ma) + (a-ma)(b-mb) > > Mathematica gives: > > b(a-ma) + ma(b-mb) + ma*mb > > Whaddup?? > > Thanks, > Kris Preacher > UNC > >