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newbie problem with differential equation

  • To: mathgroup at smc.vnet.net
  • Subject: [mg59480] newbie problem with differential equation
  • From: Daniele Lupo <danwolf80_no_spam_please_ at libero.it>
  • Date: Wed, 10 Aug 2005 02:58:08 -0400 (EDT)
  • Sender: owner-wri-mathgroup at wolfram.com

Hi.

I've a problem with a differential equation. It's

lin = y'[t] + t^2y[t] == t

If I solve it with a particular boundary value:

par = DSolve[{lin, y[0] == 3}, y, t]

I obtain a solution but, when I try to verify the initial condition:

y[0] /. par[[1]]

I've obtain a 1/0 expression, instead that bounday value that I've defined
in DSolve.

What's wrong in my workflow? It's a particular kind of differential
equation? If I put instead y[1] == 3 in che DSolve command, all works ok.
But in this case I think that Mathematica must be return a warning saying
that some branch of solution cannot verify the boundary value, I think,
instead to return an inconsistent result when I put y[0] == 3 in my
boundary value...

Thanks for answers.


Daniele (using ver 5.5.1 Student)


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