Practice Indirect Proof Methods (10.1.3) - Proof Strategies-I - Discrete Mathematics

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6 sample questions

Question 1.
What is proof by contrapositive?
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Think about how negation affects implications.
Question 2.
If p is false, what can you say about the implication p → q?
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Remember the role of false premises in implications.
3Question 3.
What does proof by contrapositive prove?
- p → q
- ¬q → ¬p
- p ∧ q
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Think about how negation affects the flow of logic.
4Question 4.
True or False: A vacuous proof can be applied even if the conclusion is false.
- True
- False
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Reflect on definitions of vacuous statements.
Question 5.
Prove that for all integers n, if n² is odd, then n is odd using contradiction.
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Focus on rephrasing even numbers.
Question 6.
Use induction or contradiction to show there are infinitely many primes.
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Think about properties of prime numbers.

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