Metamath Proof Explorer


Theorem norasslem2

Description: This lemma specializes biimt suitably for the proof of norass . (Contributed by Wolf Lammen, 18-Dec-2023)

Ref Expression
Assertion norasslem2
|- ( ph -> ( ps <-> ( ( ph \/ ch ) -> ps ) ) )

Proof

Step Hyp Ref Expression
1 orc
 |-  ( ph -> ( ph \/ ch ) )
2 biimt
 |-  ( ( ph \/ ch ) -> ( ps <-> ( ( ph \/ ch ) -> ps ) ) )
3 1 2 syl
 |-  ( ph -> ( ps <-> ( ( ph \/ ch ) -> ps ) ) )