Metamath Proof Explorer


Theorem raleqbii

Description: Equality deduction for restricted universal quantifier, changing both formula and quantifier domain. Inference form. (Contributed by David Moews, 1-May-2017)

Ref Expression
Hypotheses raleqbii.1 ⊢ A = B
raleqbii.2 ⊢ ψ ↔ χ
Assertion raleqbii ⊢ ∀ x ∈ A ψ ↔ ∀ x ∈ B χ

Proof

Step Hyp Ref Expression
1 raleqbii.1 ⊢ A = B
2 raleqbii.2 ⊢ ψ ↔ χ
3 1 eleq2i ⊢ x ∈ A ↔ x ∈ B
4 3 2 imbi12i ⊢ x ∈ A → ψ ↔ x ∈ B → χ
5 4 ralbii2 ⊢ ∀ x ∈ A ψ ↔ ∀ x ∈ B χ