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A comment on The Math Myth. Parent comment

Re:The Math Myth by iopq on Saturday September 03, 2016 @09:26AM (#12419111)
It's not a reduction. If you try to find where to put 0.999... on the number line, it has to go exactly where 1 is.

For one thing, 1 - 0.999... = 0.000... because you never get to have any remainder since 0.999... is infinite.

Or here's another proof:

x = 0.999...

10x = 9.999...

10x - x = 9.999... - 0.999...

9x = 9.000... = 9

9x = 9

x = 1

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Re:The Math Myth by kazinator on Saturday September 03, 2016 @10:53AM (#12419400)
Your "proofs" simply assumes that 0.999... is a notation denoting 1, without examining the underpinnings which might legitimize that.

9.999.. - 0.999 is 9 no matter how we define .999... just as long as two or more occurrences of the 0.999... notation all denote the same entity, and we understand that the syntax 9.999... is 9 + 0.999...

For example, if we define 0.999... as "rubber duck" then 9.999... stands for 9 + "rubber duck", and 9.999... - 0.999... stands for 9 + "rubber duck" - "rubber duck" = 9.

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Re:The Math Myth by iopq on Sunday September 04, 2016 @08:09AM (#12423930)
While that's true, the whole key to the proof is that

0.999... * 10 = 9.999...

Because "one less 9 than infinity is still infinity" it's what really closes the loop on the proof.

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