Propositional Logic


Q1.

The number of arrangements of six identical balls in three identical bins is ____.
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Q2.

Consider the following expressions: (i) false (ii) Q (iii) true (iv) P\vee Q (v) \neg Q \vee P The number of expressions given above that are logically implied by P \wedge (P \Rightarrow Q) is ________.
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Q3.

Consider the two statements. S1: There exist random variables X and Y such that \left(\mathbb E[(X-\mathbb E(X))(Y-\mathbb E(Y))]\right)^2 > \textsf{Var}[X]\textsf{Var}[Y] S2: For all random variables X and Y, \textsf{Cov}[X,Y]=\mathbb E \left[|X-\mathbb E[X]||Y-\mathbb E[Y]|\right ] Which one of the following choices is correct?
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Q4.

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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Q5.

Which one of the following well formed formulae is a tautology?
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Q6.

Which one of the following Boolean expressions is NOT a tautology?
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Q7.

Let p and q be two propositions. Consider the following two formulae in propositional logic. S1: (\neg p\wedge(p\vee q))\rightarrow qS2: q\rightarrow(\neg p\wedge(p\vee q))Which one of the following choices is correct?
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Q8.

Which one of the following predicate formulae is NOT logically valid? Note that W is a predicate formula without any free occurrence of x.
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Q9.

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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Q10.

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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