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d^2 Q(i)        Q(i+1)-2Q(i)+Q(i-1)       dQ(i)
-------- = C^2(--------------------) - b -----
dt^2              (deltx)^2              dt

         .         .      .
(Q(i+1))-2(Q(i))+(Q(i-1))
- b(i)(---------------------------)
(deltx)^2

         Q(i-1)  Q(i)  Q(i+1)
+=====+=====+=====+=====+=====+=====+   ex:N=7
deltx


The question is to solve the Q(i)

where
deltx = L/(N-1)
where L is the length of cod.
C=1
b=0
b(i)=0--1
Q(1) = sin(2t)
Q(N)=0



Thanks a lot!

[edited by - safe on August 17, 2003 10:13:19 PM]   

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2. I''m not even looking at it until you format it properly. Use the [ code] tags to preserve the spacing.

Cédric

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Sorry, lost interest on the third open bracket, but....

"(L is the length of cod.)"

Stevie

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Thanks Cedric and stevie56!
I have modified.

[edited by - safe on August 16, 2003 9:06:41 PM]

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Thank you for formatting it properly. Now, it''s quite clear that you''re asking the solution of a typical textbook problem, probably for a homework. If not, please read the Forum FAQ first anyway.

Either ways: this really is a textbook "N coupled oscillators" problem (I know; I have it right in front of me). There are dozens of site that explain how to solve such problem.

Cédric

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Thank you very much, Cedric!
I am doing a project, the professor asks me to use this in a motor control system.
I don't have enough knowledge to solve this.
The Q(i), Q(i-1) and Q(i+1) all are unknown, I don't think it's easy for me.
I apprecialte for your help if you can teach me how to solve.
Thanks a lot.

[edited by - safe on August 18, 2003 9:12:46 AM]

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