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    (Original post by elpaw)
    there is a "proof" but not a proof.
    Now that is worrying for Maths sake...
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    (Original post by bono)
    Now that is worrying for Maths sake...
    the "proof" isn't a proof because it's faulty.
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    (Original post by elpaw)
    there is a "proof" but not a proof.
    Its more of a trick isn't it? Taking 0 to be a non variable or is it a constant? So the trick suceeds
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    (Original post by elpaw)
    the "proof" isn't a proof because it's faulty.
    Is it mathematically incorrect then?
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    (Original post by 2776)
    Its more of a trick isn't it? Taking 0 to be a non variable or is it a constant? So the trick suceeds
    Could you show me this?
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    let a = b
    => a² = ab
    => a² + a²-2ab = ab + a²-2ab
    => 2(a²-ab) = (a²-ab)
    => 2 = 1
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    Just for the dim-witted amongst us, the problem with elpaw's "proof" is that a^2-ab=0 as a=b. You can't divide by zero and get a defined answer.
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    (Original post by chrisbphd)
    Just for the dim-witted amongst us, the problem with elpaw's "proof" is that a^2-ab=0 as a=b. You can't divide by zero and get a defined answer.
    i know. i already said it was incorrect.
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    You might find this interesting.

    Classic Fallacies
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    (Original post by elpaw)
    let a = b
    => a² = ab
    => a² + a²-2ab = ab + a²-2ab
    => 2(a²-ab) = (a²-ab)
    => 2 = 1


    Ahhh yes, I see now Chris!!
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    Of course, both sides equal zero, which means that the proof doesnt hold. But its quite clever anyway.
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    (Original post by elpaw)
    i know. i already said it was incorrect.
    I wasn't disputing that...I was just explaining to others.
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    (Original post by chrisbphd)
    I wasn't disputing that...I was just explaining to others.
    Me too.
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    That ladder thing is pretty sweet. But it is more of a physical thing than theoretical.
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    (Original post by elpaw)
    let a = b
    => a² = ab
    => a² + a²-2ab = ab + a²-2ab
    => 2(a²-ab) = (a²-ab)
    => 2 = 1
    Bono doesn't seem to get it:

    First line is multiplying both sides by a
    Then add (a²-2ab) to both sides
    Then simplify
    Then divide both sides by a²-2ab
    BUT dividing by a²-2ab is dividing by 0 if a=b, so you get an undefined on both sides, not 2 and 1.
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    (Original post by ZJuwelH)
    Bono doesn't seem to get it:

    First line is multiplying both sides by a
    Then add (a²-2ab) to both sides
    Then simplify
    Then divide both sides by a²-2ab
    BUT dividing by a²-2ab is dividing by 0 if a=b, so you get an undefined on both sides, not 2 and 1.
    Cheers.
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    (Original post by chrisbphd)
    You might find this interesting.

    Classic Fallacies
    the "all people in canada are the same age" one is really compelling.
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    4.45 isn't it obvious?
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    (Original post by elpaw)
    the "all people in canada are the same age" one is really compelling.
    Yeah I liked that, I got it straight away, what if G is just P and Q, I'm a logical genius!... OK maybe not...
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    (Original post by ogs)
    4.45 isn't it obvious?
    apparently it isnt, because it's 4.44
 
 
 
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