Re: [R] can R solve these paired equations

From: Robin Hankin <r.hankin_at_noc.soton.ac.uk>
Date: Mon, 17 Dec 2007 08:24:10 +0000

Hello

[An answer was posted just now using numerical ideas; here is an answer from a symbolic perspective]

These equations involve x^y in more than one unknown, so inverse functions cannot be used.

I do not think you will be able to characterize even the number of solutions, let alone their nature.

To see the difficulty, look at the Lambert W function.

My advice would be to simplify, simplify, simplify your problem as far as possible; remove terms successively until you are left with a trivial system, then add *one* term and see if
this produces any insights.

HTH rksh

On 17 Dec 2007, at 05:43, Xin wrote:

> Dear:
>
>
>
> I have a paired equation below. Can I solve (x,y) using R.
>
>
>
> Thanks!
>
>
>
> Xin
>
>
>
> A=327.727
>
> B=9517.336
>
> p=0.114^10
>
>
>
> (1-p)*y*(1-x)/x/(1-x^y)=A
>
> A(1+(1-x)*(1+y)/x-A))=B
>
>
>
>
>
> [[alternative HTML version deleted]]
>
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--
Robin Hankin
Uncertainty Analyst and Neutral Theorist,
National Oceanography Centre, Southampton
European Way, Southampton SO14 3ZH, UK
  tel  023-8059-7743

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Received on Mon 17 Dec 2007 - 08:29:46 GMT

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