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  • To: mathgroup at
  • Subject: [mg35140] RSolve
  • From: Matthias.Bode at
  • Date: Tue, 25 Jun 2002 19:55:31 -0400 (EDT)
  • Sender: owner-wri-mathgroup at

Hello Andrew,

straight from the Help Browser:

1.)  y = a, t = n.
2.) Input:
RSolve[a[n + 2] - 2*a[n + 1] + 3*a[1] == 4, a[n], n]
3.) Output:
{{a[n] -> 
    If[n >= 1, 
     2 (-2 + 2 ) - 
      (-3 + 2 ) C[1], 0]}}

Simple, isn't it?

Best regards,

Matthias Bode.

I'm new to Mathematica and am having trouble with inputting the
equations I'm looking to solve. I know the basic input of RSolve, but
can't quite get it. Here's a sample problem, if anyone could show me
how to input into RSolve I can probably run with the ball after that.

y(t+2) - 2Y(t+1) + 3Y(1) = 4

With the part in brackets being a subscript denoting time. I know it
sounds dumb, but I just don't know the input notatin well enough to
get a problem typed in correctly, and the Mathematica book is a little

Any help greatly appreciated!


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