Practice9: Problem 10 Previous Problem Problem List Next Problem (3 points) Complete the following proof, which proves the statement by contradiction: If a2 is even, then a is even. proof. Let a2 be and a be By the definition of odd, there exist integers k such that It follows that a2 = (2k + 1)2 = 4k2 + 4k+ 1 = 2( )+1. Since is an integer, and integers are closed under and , must be an integer. Thus, by the definition of odd, is odd. Hence, is odd. This contradicts with that is . Hence, the assumption that a2 is even and a is odd is false. El Note: You can earn partial credit on this problem. Preview My Answers Submit Answers You have attempted this problem 0 times. You have unlimited attempts remaining