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What is wrong in the proof? 1 = 0

Tuesday, June 13, 2006

Of course 1 != 0, spot the error.

let x = y and x² = xy

now subtracting y² from both sides, we get

x² - y² = xy - y²

(x + y)(x - y) = y(x - y)

hence x + y = y

Also, x = y then

2y = y

2 = 1

now subtracting 1 from both sides

1 = 0


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  • 5 Comments:

    At 11:07 AM,Anonymous Anonymous said...

    my take:

    (x+y)(x-y)=y(x-y)

    hence (x+y)=y

    this is a wrong step.we cant divide lhs and rhs by (x-y),until and unless x-y is not equal to zero.this gives us the supposedly paradoxical proof.

    will wait for ur response,

    regards,
    Arnab

     
    At 3:37 PM,Blogger Anup said...

    I will take it from this point of your proof:

    (x + y)(x - y) = y(x - y) - Eq. a.

    And then you go onto say that

    (x + y)= y

    This is wrong as x=y.

    Now if u use eq a with the above observation you will get
    (x+y) * 0 = y * 0

    Now anybody knows that u cannot take 0 as a common factor and cancel them on both sides of the equation. If that was the case then we could have just done

    6 * 0 = 5 * 0

    and proved 6=5.

    So thats the mistake in ur proof.

    Bye
    Anup Rajan

     
    At 2:25 PM,Anonymous Anonymous said...

    Its like dividing or multiplying both sides by Zero...in when U do that...U can take any no. in consideration!

     
    At 3:12 PM,Anonymous Anonymous said...

    when you solve it,

    (x-y) is same as (x-x) or (y-y)...
    i.e., since x=y, (x-y)=0...

    therefore, both rhs and lhs of your proof are zero...
    hence, it turns out: 0=0... (perfect!...)...

     
    At 8:58 PM,Blogger Unknown said...

    (x+y)(x-y)=y(x-y)
    implies
    either x+y=y if x!=y
    and x-y=0 if x=y
    Since x=y holds true
    therefore, x-y=0
    i.e x=y which is true
    nor x+y=y

     

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