What is wrong with this "proof"?"Theorem" For every positive integern, ifxandyare positive integers with max(x, y) =n,thenx=y.Basis Step: Suppose thatn= 1. If max(x, y) = 1 andxandyare positive integers, we havex= 1 andy= 1.Inductive Step: Letkbe a positive integer. Assume that whenever max(x, y) =kandxandyare positive integers, thenx=y. Now let max(x, y) =k+ 1, wherexandyare positiveintegers. Then max(x−1, y−1) =k, so by the inductive hypothesis,x−1 =y−1. Itfollows thatx=y, completing the inductive step.

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