Metamath Proof Explorer


Theorem rabbiia

Description: Equivalent formulas yield equal restricted class abstractions (inference form). (Contributed by NM, 22-May-1999) (Proof shortened by Wolf Lammen, 12-Jan-2025)

Ref Expression
Hypothesis rabbiia.1
|- ( x e. A -> ( ph <-> ps ) )
Assertion rabbiia
|- { x e. A | ph } = { x e. A | ps }

Proof

Step Hyp Ref Expression
1 rabbiia.1
 |-  ( x e. A -> ( ph <-> ps ) )
2 1 pm5.32i
 |-  ( ( x e. A /\ ph ) <-> ( x e. A /\ ps ) )
3 2 rabbia2
 |-  { x e. A | ph } = { x e. A | ps }