Description: Deduction adding a conjunct to antecedent. (Contributed by NM, 8-Jan-2006) (Proof shortened by Wolf Lammen, 25-Jun-2022)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | ad4ant3.1 | |- ( ( ph /\ ps /\ ch ) -> th ) |
|
| Assertion | 3adant2r | |- ( ( ph /\ ( ps /\ ta ) /\ ch ) -> th ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ad4ant3.1 | |- ( ( ph /\ ps /\ ch ) -> th ) |
|
| 2 | simpl | |- ( ( ps /\ ta ) -> ps ) |
|
| 3 | 2 1 | syl3an2 | |- ( ( ph /\ ( ps /\ ta ) /\ ch ) -> th ) |