Propositional Logic


Q41.

The binary operator \neq is defined by the following truth table. Which one of the following is true about the binary operator \neq?
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Q42.

Choose the correct choice(s) regarding the following proportional logic assertion S:S: (( P \wedge Q) \rightarrow R) \rightarrow (( P \wedge Q) \rightarrow (Q \rightarrow R))[MSQ]
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Q43.

Consider the statement "Not all that glitters is gold" Predicate glitters(x) is true if x glitters and predicate gold(x) is true if x is gold. Which one of the following logical formulae represents the above statement?
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Q44.

Consider the first-order logic sentence F:\forall x(\exists yR(x,y)). Assuming non-empty logical domains, which of the sentences below are implied by F? I. \exists y(\exists xR(x,y)) II. \exists y(\forall xR(x,y)) III. \forall y(\exists xR(x,y)) IV. \neg \exists x(\forall y\neg R(x,y))
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Q45.

Which one of the following well formed formulae is a tautology?
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Q46.

What is the logical translation of the following statement? "None of my friends are perfect."
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Q47.

Consider the following statements: P: Good mobile phones are not cheap Q: Cheap mobile phones are not good L: P implies Q M: Q implies P N: P is equivalent to Q Which one of the following about L, M, and N is CORRECT?
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Q48.

Which one of the following Boolean expressions is NOT a tautology?
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Q49.

Geetha has a conjecture about integers, which is of the form\forall x\left [P(x)\Rightarrow \exists yQ(x,y) \right ] where P is a statement about integers, and Q is a statement about pairs of integers. Which of the following (one or more) option(s) would imply Geetha's conjecture?
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Q50.

Consider the first-order logic sentence \varphi \equiv \exists s\exists t\exists u\forall v\forall w\forall x\forall y\varphi (s,t,u,v,w,x,y) where \varphi (s,t,u,v,w,x,y) is a quantifier-free first-order logic formula using only predicate symbols, and possibly equality, but no function symbols. Suppose \varphi has a model with a universe containing 7 elements. Which one of the following statements is necessarily true?
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