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Re: solve the following problem


In article <edqr42$t4p$1 at smc.vnet.net>,
 Alexandr Alexandr <a223253100 at yahoo.com> wrote:

> How would I solve the following problem with
> Mathematica? 
> x'(t) + x(t-1) = 0.

Well, it is easy to verify that

  c E^(t ProductLog[-1])

satisfies the equation for arbitrary c as follows,

  x'[t] + x[t-1] == 0 /. 
    x -> Function[t, c E^(t ProductLog[-1])] // FullSimplify

I think you need to specify the problem more completely ...

Cheers,
Paul

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Paul Abbott                                      Phone:  61 8 6488 2734
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