Logical Equivalence Flashcards
Identity Law 1
p ∧ T ≡ p
Identity Law 2
p ∨ F ≡ p
Domination Law 1
p ∨ T ≡ T
Domination Law 2
p ∧ F ≡ F
Idempotent Law 1
p ∨ p ≡ p
Idempotent Law 2
p ∧ p ≡ p
Double Negation Law
¬(¬p) ≡ p
Negation Law 1
p ∨ ¬p ≡ T
Negation Law 2
p ∧ ¬p ≡ F
Commutative Law 1
p ∨ q ≡ q ∨ p
Commutative Law 2
p ∧ q ≡ q ∧ p
Associative Law 1
(p ∨ q) ∨ r ≡ p ∨ (q ∨ r)
Associative Law 2
(p ∧ q) ∧ r ≡ p ∧ (q ∧ r)
Distributive Law 1
p ∨ (q ∧ r) ≡ (p ∨ q) ∧ (p ∨ r)
Distributive Law 2
p ∧ (q ∨ r) ≡ (p ∧ q) ∨ (p ∧ r)
Absorption Law 1
p ∨ (p ∧ q) ≡ p
Absorption Law 2
p ∧ (p ∨ q) ≡ p
De Morgan’s Law 1
¬(p ∧ q) ≡ ¬p ∨ ¬q
De Morgan’s Law 2
¬(p ∨ q) ≡ ¬p ∧ ¬q
Conditional 1
p → q ≡ ¬p ∨ q
Conditional 2
p → q ≡ ¬q → ¬p
Conditional 3
p ∨ q ≡ ¬p → q
Conditional 4
p ∧ q ≡ ¬(p → ¬q)
Conditional 5
¬(p → q) ≡ p ∧ ¬q
Conditional 6
(p → q) ∧ (p → r) ≡ p → (q ∧ r)
Conditional 7
(p → r) ∧ (q → r) ≡ (p ∨ q) → r
Conditional 8
(p → q) ∨ (p → r) ≡ p → (q ∨ r)
Conditional 9
(p → r) ∨ (q → r) ≡ (p ∧ q) → r
Biconditional 1
p ↔ q ≡ (p → q) ∧ (q → p)
Biconditional 2
p ↔ q ≡ ¬p ↔ ¬q
Biconditional 3
p ↔ q ≡ (p ∧ q) ∨ (¬p ∧ ¬q)
Biconditional 4
¬(p ↔ q) ≡ p ↔ ¬q