Metamath Proof Explorer


Theorem 3an4ancom24

Description: Commutative law for a conjunction with a triple conjunction: second and forth positions interchanged. (Contributed by AV, 18-Feb-2022)

Ref Expression
Assertion 3an4ancom24
|- ( ( ( ph /\ ps /\ ch ) /\ th ) <-> ( ( ph /\ th /\ ch ) /\ ps ) )

Proof

Step Hyp Ref Expression
1 an4com24
 |-  ( ( ( ph /\ ps ) /\ ( ch /\ th ) ) <-> ( ( ph /\ th ) /\ ( ch /\ ps ) ) )
2 3an4anass
 |-  ( ( ( ph /\ ps /\ ch ) /\ th ) <-> ( ( ph /\ ps ) /\ ( ch /\ th ) ) )
3 3an4anass
 |-  ( ( ( ph /\ th /\ ch ) /\ ps ) <-> ( ( ph /\ th ) /\ ( ch /\ ps ) ) )
4 1 2 3 3bitr4i
 |-  ( ( ( ph /\ ps /\ ch ) /\ th ) <-> ( ( ph /\ th /\ ch ) /\ ps ) )