Concept explainers
Let T be the statement: The sum of any two rational numbers is rational. Then T is true but the following “proof” is incorrect. Find the mistake.
“Proof” by contradiction: Suppose not. That is, suppose that the sum of any two rational numbers is not rational. This means that no matter what two rational numbers are chosen their sum is not rational. Now both 1 and 3 are rational because 1=1/1 and
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Chapter 4 Solutions
Discrete Mathematics With Applications
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