Description: Disjunction of three antecedents (deduction). (Contributed by NM, 14-Oct-2005)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | 3jaod.1 | |- ( ph -> ( ps -> ch ) ) |
|
| 3jaod.2 | |- ( ph -> ( th -> ch ) ) |
||
| 3jaod.3 | |- ( ph -> ( ta -> ch ) ) |
||
| Assertion | 3jaod | |- ( ph -> ( ( ps \/ th \/ ta ) -> ch ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 3jaod.1 | |- ( ph -> ( ps -> ch ) ) |
|
| 2 | 3jaod.2 | |- ( ph -> ( th -> ch ) ) |
|
| 3 | 3jaod.3 | |- ( ph -> ( ta -> ch ) ) |
|
| 4 | 3jao | |- ( ( ( ps -> ch ) /\ ( th -> ch ) /\ ( ta -> ch ) ) -> ( ( ps \/ th \/ ta ) -> ch ) ) |
|
| 5 | 1 2 3 4 | syl3anc | |- ( ph -> ( ( ps \/ th \/ ta ) -> ch ) ) |