Metamath Proof Explorer


Theorem hb3anOLD

Description: Obsolete version of hb3an as of 23-Oct-2026. (Contributed by NM, 14-Sep-2003) (Proof shortened by Wolf Lammen, 2-Jan-2018) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Hypotheses hbOLD.1 ⊢ φ → ∀ x φ
hbOLD.2 ⊢ ψ → ∀ x ψ
hbOLD.3 ⊢ χ → ∀ x χ
Assertion hb3anOLD ⊢ φ ∧ ψ ∧ χ → ∀ x φ ∧ ψ ∧ χ

Proof

Step Hyp Ref Expression
1 hbOLD.1 ⊢ φ → ∀ x φ
2 hbOLD.2 ⊢ ψ → ∀ x ψ
3 hbOLD.3 ⊢ χ → ∀ x χ
4 1 nf5i ⊢ Ⅎ x φ
5 2 nf5i ⊢ Ⅎ x ψ
6 3 nf5i ⊢ Ⅎ x χ
7 4 5 6 nf3an ⊢ Ⅎ x φ ∧ ψ ∧ χ
8 7 nf5ri ⊢ φ ∧ ψ ∧ χ → ∀ x φ ∧ ψ ∧ χ