Description: Absorption into embedded conjunct. (Contributed by NM, 20-Jul-1996) (Proof shortened by Wolf Lammen, 17-Nov-2013)
Ref | Expression | ||
---|---|---|---|
Assertion | anabs7 | |- ( ( ps /\ ( ph /\ ps ) ) <-> ( ph /\ ps ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | simpr | |- ( ( ph /\ ps ) -> ps ) |
|
2 | 1 | pm4.71ri | |- ( ( ph /\ ps ) <-> ( ps /\ ( ph /\ ps ) ) ) |
3 | 2 | bicomi | |- ( ( ps /\ ( ph /\ ps ) ) <-> ( ph /\ ps ) ) |