Thread: .9999...=1
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Old November 27th, 2012, 01:59 PM   #38 (permalink)
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Originally Posted by SUroot View Post
You can't do the maths with infinite or reccurring numbers so you must start with a set amount of digits to prove a point. An absolute number.

Multiply by 10 simply moves the decimal point. It can't conveniently make more digits or decimal places

X = .999999
10x = 9.99999

10x - x = 9x


9.99999 - .999999 = 8.999991

Its not so much that your maths is wrong as it is that maths is wrong in general.
This as written is correct, but fails to take into account that .999... a number of infinite length. Thus require the use of an infinite limit. I'll post the calculus proof by use of infinite series, since there is still non believers once I finish teaching my last class tonight.
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