Description: Inference conjoining and disjoining the antecedents of two implications. (Contributed by NM, 30-Sep-1999)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | jaao.1 | |- ( ph -> ( ps -> ch ) ) |
|
| jaao.2 | |- ( th -> ( ta -> ch ) ) |
||
| Assertion | jaao | |- ( ( ph /\ th ) -> ( ( ps \/ ta ) -> ch ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | jaao.1 | |- ( ph -> ( ps -> ch ) ) |
|
| 2 | jaao.2 | |- ( th -> ( ta -> ch ) ) |
|
| 3 | 1 | adantr | |- ( ( ph /\ th ) -> ( ps -> ch ) ) |
| 4 | 2 | adantl | |- ( ( ph /\ th ) -> ( ta -> ch ) ) |
| 5 | 3 4 | jaod | |- ( ( ph /\ th ) -> ( ( ps \/ ta ) -> ch ) ) |