Description: Conjunction form of e12 (see syl6an ). (Contributed by Alan Sare, 11-Jun-2011) (Proof modification is discouraged.) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | e12an.1 | |- (. ph ->. ps ). | |
| e12an.2 | |- (. ph ,. ch ->. th ). | ||
| e12an.3 | |- ( ( ps /\ th ) -> ta ) | ||
| Assertion | e12an | |- (. ph ,. ch ->. ta ). | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | e12an.1 | |- (. ph ->. ps ). | |
| 2 | e12an.2 | |- (. ph ,. ch ->. th ). | |
| 3 | e12an.3 | |- ( ( ps /\ th ) -> ta ) | |
| 4 | 3 | ex | |- ( ps -> ( th -> ta ) ) | 
| 5 | 1 2 4 | e12 | |- (. ph ,. ch ->. ta ). |