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

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 Ian A. Mason Posts: 18 Registered: 12/12/04
Re: -1 x -1 ?
Posted: Sep 16, 1999 5:42 PM

let b be the additive inverse of 1 (aka -1)

thus:

b+1 = 0

thus (squaring both sides):

(b+1)(b+1) = 0

thus (multiplying out and using commutativity)

b*b + 2b + 1 = 0

thus

b*b + b + (b + 1) = 0

thus:

b*b + b + 0 = 0

thus

b*b + b = 0

b*b is the additive inverse of b (aka 1).

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