Propositional Logic Quiz

What is the main purpose of propositional logic?

• To express the relationships between objects

• To study the truth values of propositions

• To represent data structures

• To manipulate numbers

Which of the following is a valid proposition?

• 3 + 2 = 5

• What time is it?

• x + 3 = 7

• Close the door

A statement that is always true is called a:

• Contradiction

• Tautology

• Contingency

• Proposition

Which of the following is not a logical connective?

• AND

• OR

• IMPLIES

• EQUALS

Which law states that "¬(p ∧ q) ≡ (¬p ∨ ¬q)"?

• De Morgan's law

• Idempotent law

• Associative law

• Commutative law

Two propositions are said to be logically equivalent if:

• They have the same truth values

• They are tautologies

• They contradict each other

• They have different truth tables

Which of the following is an example of a tautology?

• p ∨ ¬p

• p ∧ ¬p

• p → q

• q → ¬q

The contrapositive of "If p then q" is:

• If ¬p then ¬q

• If q then p

• If ¬q then ¬p

• If p then ¬q

A valid argument is one where:

• The conclusion is always false

• The premises and conclusion are both true

• The conclusion logically follows from the premises

• The premises are contradictory

Which of the following is a rule of inference?

• Tautology

• Modus Ponens

• Contingency

• Negation