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Topic: -1 x -1 ?
Replies: 29   Last Post: May 13, 2009 9:01 AM

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 Peter Percival Posts: 339 Registered: 12/6/04
Re: -1 x -1 ?
Posted: Sep 18, 1999 8:45 AM

Dale Henderson wrote:

> In article <937516347.13527.0.nnrp-14.c2debf68@news.demon.co.uk>,
> "Guillermo Phillips" <Guillermo.Phillips@marsman.demon.co.uk> wrote:

> > Hello All,
> >
> > Here's something I've always wondered (perhaps in my naivety). Why
> > should -1 x -1 = 1?
> > I appreciate that lots of nice things come from this, but what's the
> > fundamental reason for it?
> >
> > Guillermo.
> >
> >

>
> I've seen a few proofs on this thread that make unfounded assumtions.
> One assumes the uniqness of inverses and another assumes 0x=0.

<cut>

Well, we won't get far without "unfounded assumptions" will we? I assumed
we were working in a ring in which my "unfounded assumptions" do hold.

<cut>I've tried to assume only the axioms of a Ring...

Date Subject Author
9/16/99 Guillermo Phillips
9/16/99 Ian A. Mason
9/16/99 Peter Percival
9/16/99 Dave Seaman
9/17/99 Steve Leibel
9/17/99 Dale Henderson
9/18/99 Peter Percival
9/18/99 Bill Taylor
9/18/99 John Savard
9/19/99 carel
9/20/99 Jon Haugsand
9/20/99 HH
9/20/99 Jon Haugsand
9/20/99 Jonathan Hoyle
9/20/99 Jim Hunter
1/21/09 Tay
1/21/09 mensanator
1/21/09 lwalke3@lausd.net
1/22/09 Henry
1/22/09 David R Tribble
1/22/09 Dave L. Renfro
1/22/09 mensanator
5/12/09 Kayama
5/12/09 mensanator
5/12/09 hagman
5/12/09 Bill Dubuque
5/12/09 Bill Taylor
5/13/09 Cobra
5/13/09 Cobra