Consider the following proposed proof by contradiction that for all positive integers n, 3n > 2. Proof by Contradiction: Suppose that the statement is false. Since n is a positive integer, n ⥠1. That means 3n ⥠3 > 2. Thus the statement is true. The fact that the statement is true contradicts the assumption that the statement is false. Thus, the assumption that the statement was false must have been false. Thus, the statement is true. a. This is what the lecture calls a 'Take proof by contradiction"
b. The proof contains a simple direct proof, wrapped inside the unnecessary logical packaging of a proof by contradiction framework.
c. The proof is not technically incorrect, but it is nevertheless an example of extremely bad proof writing.