Commutative laws

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Commutative laws

The commutative laws state that the order of propositions does not affect the truth value of conjunction or disjunction.

Statements

  • p ∧ q ≡ q ∧ p
  • p ∨ q ≡ q ∨ p

Explanation

The logical value of a conjunction or disjunction remains unchanged when the order of the operands is swapped.

Examples

  • "I study AND I pass the exam" is equivalent to "I pass the exam AND I study".
  • "It rains OR it snows" is equivalent to "It snows OR it rains".

Truth Table (Conjunction)

p q p ∧ q q ∧ p
T T T T
T F F F
F T F F
F F F F

Truth Table (Disjunction)

p q p ∨ q q ∨ p
T T T T
T F T T
F T T T
F F F F