Résolution

∀x. A ≡ ¬∃x. ¬A
¬∀x. A ≡ ∃x. ¬A
∃x. A ≡ ¬∀x. ¬A
¬∃x. A ≡ ∀x. ¬A
∀x. (A∧B)≡ ∀x. A ∧ ∀x. B
∃x. (A∨B)≡ ∃x. A ∨ ∃x. B
∃x. (A→B)≡ ∀x. A → ∃x. B
∀x. ∀y. A ≡ ∀y. ∀x. A
∃x. ∃y. A ≡ ∃y. ∃x. A

x /∈V I(A)
∀x. A ≡ ∃x. A ≡A
∀x. (A∧B)≡A∧ ∀x. B
∃x. (A∧B)≡A∧ ∃x. B
∀x. (A∨B)≡A∨ ∀x. B
∃x. (A∨B)≡A∨ ∃x. B
∃x. (A→B)≡A→ ∃x. B
∀x. (A→B)≡A→ ∀x. B
∃x. (B→A)≡ ∀x. B →A
∀x. (B→A)≡ ∃x. B →A

G
Q1x1. . . QnxnA Qi
∀ ∃ A
G G0
G≡G0

G
∀x1. . . ∀xn∃xn+1Qn+2xn+2Qn+ixn+iAf
n
∀x1. . . ∀xnQn+2xn+2Qn+ixn+iA{xn+1/f(x1, . . . , xn)}
G
G G0
G G0