Description: Simplification of triple conjunction. (Contributed by NM, 21-Apr-1994) (Proof shortened by Wolf Lammen, 21-Jun-2022)
Ref | Expression | ||
---|---|---|---|
Assertion | 3simpa | |- ( ( ph /\ ps /\ ch ) -> ( ph /\ ps ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | id | |- ( ( ph /\ ps ) -> ( ph /\ ps ) ) |
|
2 | 1 | 3adant3 | |- ( ( ph /\ ps /\ ch ) -> ( ph /\ ps ) ) |