Unformatted text preview: From Section 1.2: problems 2, 3, 4, 5, 6, 8, 9, 12, 16, 19, 20, 37, 46 Additional problems on entailment: Suppose we assume the logic has just 5 statement letters: A, B, C, D, and E. E1. How many models are there for the formula A ^ B? E2. How many models are there for the formula B > (not C)? E3. Show a model that is a counterexample to (A ^ B) = (B > (not C))? E4. Expand the definition of entailment in the following two statements, explaining without using "entails" what they mean: a. P = (Q v R) b. either (P = Q) or (P = R) or both Here, P, Q, and R are arbitrary formulas. E5. Prove that 4a and 4b are not necessarily the same by finding formulas P, Q, and R for which one is true and the other is false....
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 Spring '08
 BAGCHI

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