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MathGroup Archive 2001

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Re: Mathematica 3.0, 4.0, 4.1 differences in DSolve[]

  • To: mathgroup at smc.vnet.net
  • Subject: [mg26723] Re: Mathematica 3.0, 4.0, 4.1 differences in DSolve[]
  • From: "Paul Lutus" <nospam at nosite.com>
  • Date: Fri, 19 Jan 2001 02:14:03 -0500 (EST)
  • References: <93r9d2$52v@smc.vnet.net> <MOu96.2591$nn4.77527@ralph.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

"Jens-Peer Kuska" <kuska at informatik.uni-leipzig.de> wrote in message
news:MOu96.2591$nn4.77527 at ralph.vnet.net...
> Hi,
>
>
> the solution
>
> p[t]->ip - (Log[1 + (f^2*iv^2)/a] +
>    2*Log[Cos[Sqrt[a]*f*t + I/2*Log[1 - (I*f*iv)/Sqrt[a]] -
>        I/2*Log[1 + (I*f*iv)/Sqrt[a]]]])/(2*f^2)
>
> is correct. It is easy obtained by lowering the order
> of the equation and first solve p1'[t]==f^2*p1[t]+a
>
> One finds that Mathematica 4.0.2 (with numerous error messages)
> find thew correct solution also and the solution is correct.

Umm, you may find that 4.1 won't solve it, as I have (unless you mean the
above solution was provided by 4.1). 4.0.2 is close enough to the version
that I used to solve it initially.

In any case, thanks for posting a solution!

--
Paul Lutus
www.arachnoid.com





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