Re: How to get the real and imaginary parts of a power series?
- To: mathgroup at smc.vnet.net
- Subject: [mg80016] Re: How to get the real and imaginary parts of a power series?
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Fri, 10 Aug 2007 06:42:35 -0400 (EDT)
- Organization: Uni Leipzig
- References: <f9gvbc$b90$1@smc.vnet.net>
- Reply-to: kuska at informatik.uni-leipzig.de
Hi, try ComplexExpand[Re[s] // Normal] Regards Jens Gordon Smith wrote: > Suppose s = Series[Cosh[(x + I y)u, {u,0,2}]. How can I get the real part 1 + 1/2(x^2 - y^2) u^2 + O(u^3) and the imaginary part x y u^2 + O(u^3) ? I thought ComplexExpand[Re[s]] should give me the real part of s, but it just gives me s unchanged. (Mathematica newbie here!) >