1. Joined
    20 Dec '05
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    1008
    14 Feb '06 00:59
    1/3=.333....

    now multiply both sides by three

    ...and 1 = .999....


    no need for real analysis, group theory, topology, or set theory for that
  2. Joined
    07 Dec '05
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    3685
    14 Feb '06 01:24
    Wow! A third thread related to this little math problem.
    I didn't know my little argument would become such a big deal.
  3. Subscribersonhouse
    Fast and Curious
    slatington, pa, usa
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    14 Feb '06 01:29
    Originally posted by acubed123
    1/3=.333....

    now multiply both sides by three

    ...and 1 = .999....


    no need for real analysis, group theory, topology, or set theory for that
    Does 0.333.. = more or less than 0.333...?
  4. Joined
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    14 Feb '06 02:07
    Personally I like asking the question,

    What number is between the two numbers 1 and .999....?

    This number by definition would be the difference (subtraction).
  5. Joined
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    61209
    14 Feb '06 02:16
    Originally posted by Bishopcrw
    Personally I like asking the question,

    What number is between the two numbers 1 and .999....?

    This number by definition would be the difference (subtraction).
    Ah, from calculus, to high school algebra, to elementary basic math... now we're speaking my language, and I agree.
  6. Joined
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    2712
    14 Feb '06 02:19
    ok ok ok we get it, .9999999... = 1, etc. the proof is simple, any 9th grade math student is familiar with it.


    .99999....=X
    therefore:
    10 times (.9999.....) = 10X
    which equals:
    9.9999.......=10X
    so:
    9.9999....minus x = 10x - x

    which equals 9= 9X
    so 9/9 = 9x/9
    so 1 = X

    get it?
  7. Joined
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    61209
    14 Feb '06 02:29
    Originally posted by Drumbo
    ok ok ok we get it, .9999999... = 1, etc. the proof is simple, any 9th grade math student is familiar with it.


    .99999....=X
    therefore:
    10 times (.9999.....) = 10X
    which equals:
    9.9999.......=10X
    so:
    9.9999....minus x = 10x - x

    which equals 9= 9X
    so 9/9 = 9x/9
    so 1 = X

    get it?
    I like your name.
  8. Standard memberTrains44
    Full speed locomotiv
    Account suspended
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    14 Feb '06 02:45
    Originally posted by SJ247
    I like your name.
    I like yours too.😉
  9. Joined
    05 Oct '05
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    61209
    14 Feb '06 03:14
    Originally posted by TRAINS44
    I like yours too.😉
    😉
  10. Joined
    20 Dec '05
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    1008
    14 Feb '06 06:01
    Originally posted by Bishopcrw
    Personally I like asking the question,

    What number is between the two numbers 1 and .999....?

    This number by definition would be the difference (subtraction).
    there is none ..... try it 😉
  11. Joined
    07 Dec '05
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    3685
    14 Feb '06 15:191 edit
    And Acubed gets the answer correct.

    I thought a little rephrase would help some people with this. 😉

    Thanks to Drumbo for taking up the cause.

    I was about to revisit the old postulates and proofs to prove it out.

    I was quite surprised at the outburst in the community about this.
  12. Standard memberTheMaster37
    Kupikupopo!
    Out of my mind
    Joined
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    20443
    15 Feb '06 09:402 edits
    Originally posted by Bishopcrw
    Personally I like asking the question,

    What number is between the two numbers 1 and .999....?

    This number by definition would be the difference (subtraction).
    The difference you speak of is smaller than all positive numbers.

    It is not a negative number. Let's call the difference X.

    So we have
    1) 0=X or 0 is smaller than X
    2) X is smaller than p, for all positive numbers p.

    Theorem: X=0.
    Proof:

    Let's assume X is NOT equal to zero. From 1) we infer then that 0 is smaller than X

    Make P = 0.5 * X.

    0 is smaller than P clearly.

    But now we have a contradiction with 2)!

    Our assumption must then be false.

    So X=0.

    QED

    In words this means that the difference between 1 and 0.999... is zero, in other words the two numbers are equal.
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