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by:  Erik Oosterwal

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2 = 1?

If x = 1 and y = 1 then:

 x = y
Multiply both sides by x:

 x² = xy
Subtract y² from each side:

 x²-y² = xy-y²
Factor each side:

 (x+y)(x-y) = y(x-y)
Divide out the common term (x-y) from each side:

 x+y = y
Put the initial values back in place:

or
 1+1 = 1

2 = 1


What's wrong with the proof?

I give up, show me the Answer


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