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#1 Re: This is Cool » 0.9999....(recurring) = 1? » 2009-02-26 08:44:49

I have spent a while reading some of these posts and I thought I’d put in my 2 cents…
I feel as though I need to remind some people that infinity is not a number (it’s a concept). Therefore, properties of real numbers do not apply to it. So you can’t put infinity into a mathematical equations such as infinity=1*x and then add one to both sides. (You can only do that with numbers; and infinity is not a number.)
Also: as hard at it is to believe, I am convinced that .999999… does =1. (I don’t particularly like it, but I know that it is true.)

I haven’t seen this posted yet, so I thought I’d add this argument to the mix…

1/9 = .1111…
2/9 = .2222…
3/9 = .3333…
4/9 = .4444…
5/9 = .5555…
6/9 = .6666…
7/9 = .7777…
8/9 = .8888…
9/9 = .9999…

But 9/9 also = 1. So, (using substitution) 9/9 = .9999… becomes 1 = .9999…

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