Description: Conjunction form of e20 . (Contributed by Alan Sare, 15-Jun-2011) (Proof modification is discouraged.) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | e20an.1 | |- (. ph ,. ps ->. ch ). |
|
| e20an.2 | |- th |
||
| e20an.3 | |- ( ( ch /\ th ) -> ta ) |
||
| Assertion | e20an | |- (. ph ,. ps ->. ta ). |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | e20an.1 | |- (. ph ,. ps ->. ch ). |
|
| 2 | e20an.2 | |- th |
|
| 3 | e20an.3 | |- ( ( ch /\ th ) -> ta ) |
|
| 4 | 3 | ex | |- ( ch -> ( th -> ta ) ) |
| 5 | 1 2 4 | e20 | |- (. ph ,. ps ->. ta ). |