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Most Famous Maths Puzzle

Famous math PuzzleMost Famous Maths Puzzle - 3 November

I can prove why 1 = 2

* Lets say y = x
* Multiply through by x xy = x2
* Subtract y2 from each side xy - y2 = x2 - y2
* Factor each side y(x-y) = (x+y)(x-y)
* Divide both sides by (x-y) y = x+y
* Divide both sides by y y/y = x/y + y/y
* And so... 1 = x/y + 1
* Since x=y, x/y = 1 1 = 1 + 1
* And so... 1 = 2

How is this possible ?

For Solution : Click Here


  1. Division by 0 is forbidden! Once you do it the whole excercise is void.

  2. x-y is zero
    you are cancelling zero and zero
    it is not possible
    so error occurs

  3. You divided by x-y, which is 0

  4. that statement is valid, as you declared x=y. then you proved the relationship between the variables i.e. x & y. finally you represented this numerically. there are two equal variables being compared reason x+y=2.: 1=1+1 = 2.

  5. initially there is an assumption is made that,finally that is not taken as conclusion to have to be proved

  6. I can give u an easier version of the problem...
    =>1=2(diving by zero on both sides)
    following the above relation we can also prove 1=100 or 1=100000000 as I wish...
    The point is u can never divide a number by zero...thats where the problem is, isnt it??

  7. we should remember one think in life first is dont divide by zero and other is dont have any girl friend

    1. If you think remembering the first one is that important, you shouldn't have any trouble with the second.

  8. By multiplying both sides by X you add the solution X=0, by dividing by (y-x), you take out the solution y=x. therefore the last equation is still correct and with x=0 we have 1=1