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Math Forum » Discussions » sci.math.* » sci.math.independent

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

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Dave L. Renfro

Posts: 4,442
Registered: 12/3/04
Re: -1 x -1 ?
Posted: Jan 22, 2009 12:39 PM
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Tay wrote:

> -1 *-1 = 1 huh?
>
> Well, think of it like this:
>
> The minus (negative) signs cancel eachother out:
>
> (-1)(-1)=
>
> [(-)(-)](1x1)=
>
> So then, multiply the + and numbers:
>
> (+)(1x1)=
>
> You've got positive 1:
>
> +1
>
> It's so simple.

It's simpler than what you wrote. The signs don't cancel.
Indeed, this begs the question of how what exists (the two
negative signs) can change to a state of not existing.
Instead, the two negative signs combine to form a positive
sign: - - becomes, after rotating one of the negative signs
so that it is perpendicular to the other negative sign, +.

It's that simple.

Dave L. Renfro

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