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Re: Assumptions does not work in Eliminate?

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  • Subject: [mg127915] Re: Assumptions does not work in Eliminate?
  • From: Bob Hanlon <hanlonr357 at gmail.com>
  • Date: Fri, 31 Aug 2012 04:01:46 -0400 (EDT)
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  • References: <20120829051425.4BC8B687E@smc.vnet.net>

?? $Assumptions

$Assumptions is the default setting for the Assumptions option used in
such functions as Simplify, Refine, and Integrate.  >>

$Assumptions=True


Options[Eliminate, Assumptions]

Options::optnf: Assumptions is not a known option for Eliminate. >>

{}


Consequently,

$Assumptions = {b > 0};

Eliminate[{a/b == c, a == d}, a] // Simplify

b c == d


Bob Hanlon


On Thu, Aug 30, 2012 at 4:07 AM,  <"Andreas Talmon l'Arm=E9e"@smc.vnet.net> wrote:
> Hello,
>
> I am trying to use the $Assumptions command with the Eliminate in the
> following form:
>
>
> $Assumptions = {b > 0}
>
> Eliminate[{a/b == c, a == d}, a]
>
>
>
> The answer I get is:
>
> d == b c && b != 0
>
>
>
> The b!=0 is sensless for me because I stated b>0 above.
> What am I doing wrong?
>
> Thanks, Andreas
>



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