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Concept drill

tautology

GATE CSE & IT · Set Theory & Logic · 1990-2021

15
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80%
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0
elite explanations
13
years appeared

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Rosen — Discrete Mathematics and Its Applications

Discrete structures, counting, relations, graph theory

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2021 PYQ

Let p and q be two propositions. Consider the following two formulae in propositional logic. S 1 : (¬p ∧ (p ∨ q)) → q S 2 : q → (¬p ∧ (p ∨ q)) Which one of the following choices is...

easyanswer keybasic explanation
2021 PYQ

Choose the correct choice(s) regarding the following propositional logic assertion S: S : ((P ∧ Q)→ R)→ ((P ∧ Q)→ (Q → R))

easyanswer keybasic explanation
2016 PYQ

Consider the following expressions: $$\,\,\,\,\,\,\,\,\,\,\,\,\,$$ $$(i)$$ $$\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,$$ false $$\,\,\,\,\,\,\,\,\,\,\,\,$$ $$(ii)$$ $$\,\,\,\,\,\,\,\,\,\,\,\,...

medium
2014 PYQ

Which one of the following Boolean expressions is NOT A tautology?

mediumanswer key
2006 PYQ

Consider the following propositional statements: $${\rm P}1:\,\,\left( {\left( {A \wedge B} \right) \to C} \right) \equiv \left( {\left( {A \to C} \right) \wedge \left( {B \to C} \...

mediumanswer key
2005 PYQ

Let $$P, Q$$ and $$R$$ be three atomic prepositional assertions. Let $$X$$ denotes $$\left( {P \vee Q} \right) \to R$$ and $$Y$$ denote $$\left( {P \to R} \right) \vee \left( {Q \t...

mediumanswer key
2004 PYQ

The following propositional statement is $$$\left( {P \to \left( {Q \vee R} \right)} \right) \to \left( {\left( {P \wedge Q} \right) \to R} \right)$$$

mediumanswer key
2004 PYQ

Let $$p, q, r$$ and $$s$$ be four primitive statements. Consider the following arguments: $$P:\left[ {\left( {\neg p \vee q} \right) \wedge \left( {r \to s} \right) \wedge \left( {...

mediumanswer key
2002 PYQ

Determine whether each of the following is a tautology, a contradiction, or neither ("$$ \vee $$" is disjunction, "$$ \wedge $$" is conjuction, "$$ \to $$" is implication, "$$\neg...

easy
2001 PYQ

Consider two well-formed formulas in propositional logic $$F1:P \Rightarrow \neg P$$ $$F2:\left( {P \Rightarrow \neg P} \right) \vee \left( {\neg P \Rightarrow } \right)$$ Which of...

easyanswer key
2000 PYQ

Let $$a, b, c, d$$ be propositions. Assume that the equivalences $$a \leftrightarrow \left( {b \vee \neg b} \right)$$ and $$b \leftrightarrow c$$ hold. Then the truth value of the...

easyanswer key
1999 PYQ

(a) Show that the formula $$\left[ {\left( { \sim p \vee Q} \right) \Rightarrow \left( {q \Rightarrow p} \right)} \right]$$ is not a tautology. (b) Let $$A$$ be a tautology and $$B...

easy
1996 PYQ

Which one of the following is false? Read $$ \wedge $$ as AND, $$ \vee $$ as OR, $$ \sim $$ as NOT, $$ \to $$ as one way implication and $$ \leftrightarrow $$ two way implication.

easyanswer key
1992 PYQ

Which of the following is/are tautology?

easyanswer key
1990 PYQ

Indicate which of the following well-formed formula are valid:

mediumanswer key