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Question Appendix.8: Using a Counterexample Use a counterexample to show that the...

Using a Counterexample

Use a counterexample to show that the statement is false.

Every odd number is prime.

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Certainly, you can list many odd numbers that are prime (3, 5, 7, 11), but the statement above is not true, because 9 is odd but it is not a prime number. The number 9 is a counterexample.

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