Metamath Proof Explorer


Theorem bj-exlimmpbir

Description: Lemma for theorems of the vtoclg family. (Contributed by BJ, 3-Oct-2019) (Proof modification is discouraged.)

Ref Expression
Hypotheses bj-exlimmpbir.nf ⊢ Ⅎ x φ
bj-exlimmpbir.maj ⊢ χ → φ ↔ ψ
bj-exlimmpbir.min ⊢ ψ
Assertion bj-exlimmpbir ⊢ ∃ x χ → φ

Proof

Step Hyp Ref Expression
1 bj-exlimmpbir.nf ⊢ Ⅎ x φ
2 bj-exlimmpbir.maj ⊢ χ → φ ↔ ψ
3 bj-exlimmpbir.min ⊢ ψ
4 3 2 mpbiri ⊢ χ → φ
5 1 4 exlimi ⊢ ∃ x χ → φ