Metamath Proof Explorer


Theorem opnneilem

Description: Lemma factoring out common proof steps of opnneil and opnneirv . (Contributed by Zhi Wang, 31-Aug-2024)

Ref Expression
Hypothesis opnneilem.1
|- ( ( ph /\ x = y ) -> ( ps <-> ch ) )
Assertion opnneilem
|- ( ph -> ( E. x e. J ( S C_ x /\ ps ) <-> E. y e. J ( S C_ y /\ ch ) ) )

Proof

Step Hyp Ref Expression
1 opnneilem.1
 |-  ( ( ph /\ x = y ) -> ( ps <-> ch ) )
2 sseq2
 |-  ( x = y -> ( S C_ x <-> S C_ y ) )
3 2 adantl
 |-  ( ( ph /\ x = y ) -> ( S C_ x <-> S C_ y ) )
4 3 1 anbi12d
 |-  ( ( ph /\ x = y ) -> ( ( S C_ x /\ ps ) <-> ( S C_ y /\ ch ) ) )
5 4 cbvrexdva
 |-  ( ph -> ( E. x e. J ( S C_ x /\ ps ) <-> E. y e. J ( S C_ y /\ ch ) ) )