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Collection of Proofs

The following collection includes "proofs" that are correctly prepared and

those with flaws in them, proofs that can be found in the mathematical

tradition and those prepared by students. Examine the "proofs" presented

here, judge their soundness, improve on them; in short, pretend you are the

teacher and grade the material presented.

THEOREM 1.

The number 1 is the largest integer.

Alleged Proof. Suppose the conclusion is false. Then let n > 1 be the

largest integer. Multiplying both sides of this inequality by n, yields n^ > n.

This is a contradiction, because n^ is another integer larger than n. Thus, the

theorem is proved. •

THEOREM 2. The value of the expression y sysTv^^S is 3.

Alleged Proof.

Let

N sysyaVWJT^ 115

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