Propositional Logic Quiz

What are the two main components of a knowledge-based agent?

• Syntax and semantics

• Atoms and literals

• Knowledge base and inference engine

• Propositions and clauses

In propositional logic, what is an interpretation?

• A function that assigns truth values to atomic propositions

• A set of clauses

• A logical implication

• A compound proposition

Which of the following is NOT a valid connective in propositional logic?

• ∧ (and)

• ∨ (or)

• → (implies)

• ≠ (not equal)

What is a literal in propositional logic?

• Any atomic proposition

• An atomic proposition or its negation

• A compound proposition

• A clause

Which of the following statements about logical implication (A ⇒ B) is true?

• It is always false when A is false

• It is always true when B is true

• It is false only when A is true and B is false

• It is equivalent to (B ⇒ A)

What is a model of a propositional knowledge base?

• A set of clauses

• An interpretation that satisfies the knowledge base

• A logical consequence

• A truth table

Which of the following is an example of the Modus Ponens rule?

• ((A → B) ∧ A) ⇒ B

• ((A → B) ∧ ¬B) ⇒ ¬A

• ((A → B) ∧ (B → C)) ⇒ (A → C)

• (A ∧ B) ⇒ A

What does it mean for a proposition g to be a logical consequence of a knowledge base KB?

• g is true in some models of KB

• g is true in every model of KB

• g is a clause in KB

• g is logically equivalent to KB

Which of the following is NOT a valid equivalence in propositional logic?

• ¬¬A ⇔ A

• (A ∧ B) ⇔ (B ∧ A)

• (A → B) ⇔ (B → A)

• (A ∨ (B ∧ C)) ⇔ ((A ∨ B) ∧ (A ∨ C))

In the context of a propositional inference engine, what does KB ∪ Percepts |= g mean?

• KB and Percepts are logically equivalent to g

• g is a member of KB and Percepts

• g is true in all models where KB and Percepts are true

• KB and Percepts are inconsistent with g

Answer explanation

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