Practice Tautologies, Contradictions, And Contingencies (8.5)

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11 questions

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6 sample questions

Question 1.
What is a tautology?
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Think of statements that cannot be false.
Question 2.
What does a contradiction mean?
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Reflect on statements that oppose each other.
3Question 3.
What is a tautology?
- A statement that is always false
- A statement that is sometimes true
- A statement that is always true
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Look for a definition that confirms 'always'.
4Question 4.
True or False: A contradiction is always true.
- True
- False
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Reflect on what contradiction means.
Question 5.
Prove that 'P ∨ ¬P' is a tautology using a truth table.
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Fill in for P being true and false systematically.
Question 6.
Show that 'P → (Q ∨ R)' can be false by providing a specific situation.
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Consider scenarios where implications can fail.

7 more questions in this section. Enroll free to practise them all.