Description: Introduction of antecedent as conjunct. (Contributed by NM, 5-Dec-1995)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | ibar | |- ( ph -> ( ps <-> ( ph /\ ps ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | iba | |- ( ph -> ( ps <-> ( ps /\ ph ) ) ) |
|
| 2 | 1 | biancomd | |- ( ph -> ( ps <-> ( ph /\ ps ) ) ) |