Description: Conjoin antecedent to right of consequent. (Contributed by NM, 25-Jul-1999) (Proof shortened by Wolf Lammen, 24-Mar-2013)
Ref | Expression | ||
---|---|---|---|
Assertion | ancrb | |- ( ( ph -> ps ) <-> ( ph -> ( ps /\ ph ) ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | iba | |- ( ph -> ( ps <-> ( ps /\ ph ) ) ) |
|
2 | 1 | pm5.74i | |- ( ( ph -> ps ) <-> ( ph -> ( ps /\ ph ) ) ) |