Metamath Proof Explorer


Theorem rabbia2

Description: Equivalent wff's yield equal restricted class abstractions. (Contributed by Glauco Siliprandi, 26-Jun-2021)

Ref Expression
Hypothesis rabbia2.1 x A ψ x B χ
Assertion rabbia2 x A | ψ = x B | χ

Proof

Step Hyp Ref Expression
1 rabbia2.1 x A ψ x B χ
2 1 a1i x A ψ x B χ
3 2 rabbidva2 x A | ψ = x B | χ
4 3 mptru x A | ψ = x B | χ