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 ) ) |