Metamath Proof Explorer


Theorem rabbida3

Description: Equivalent wff's yield equal restricted class abstractions. (Contributed by Glauco Siliprandi, 23-Oct-2021)

Ref Expression
Hypotheses rabbida3.1 ⊢ Ⅎ x φ
rabbida3.2 ⊢ φ → x ∈ A ∧ ψ ↔ x ∈ B ∧ χ
Assertion rabbida3 ⊢ φ → x ∈ A | ψ = x ∈ B | χ

Proof

Step Hyp Ref Expression
1 rabbida3.1 ⊢ Ⅎ x φ
2 rabbida3.2 ⊢ φ → x ∈ A ∧ ψ ↔ x ∈ B ∧ χ
3 1 2 abbid ⊢ φ → x | x ∈ A ∧ ψ = x | x ∈ B ∧ χ
4 df-rab ⊢ x ∈ A | ψ = x | x ∈ A ∧ ψ
5 df-rab ⊢ x ∈ B | χ = x | x ∈ B ∧ χ
6 3 4 5 3eqtr4g ⊢ φ → x ∈ A | ψ = x ∈ B | χ