Integrals of Fourier Series
- To: mathgroup at smc.vnet.net
- Subject: [mg3179] Integrals of Fourier Series
- From: goster at nature.Berkeley.EDU (George Oster)
- Date: Tue, 13 Feb 1996 02:29:27 -0500
- Sender: owner-wri-mathgroup at wolfram.com
Suppose I want to substitue a Fourier Series into an integral:
u[x_] := Sum[A[n] Sin[n Pi x/L], {n, 1, Infinity}]
Integrate[(u''[x])^2, {x, 0, L}]
This has an easy analytical solution that I can't get Mma to find, because
Mma doesn't know that Sum and Integrate commute, and that Sin[n
Pi] = 0 for all integer n.
How to do this?
GO
_____________________________________________
Professor George Oster
University of California
201 Wellman Hall
Berkeley, CA 94720-3112
Phone & Fax: 510-642-5277
Email: goster at nature.berkeley.edu
http://www.cnr.berkeley.edu/~goster/home.html
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