Description: Syllogism combined with contraction. (Contributed by NM, 11-Mar-2012)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | syl3anc.1 | |- ( ph -> ps ) | |
| syl3anc.2 | |- ( ph -> ch ) | ||
| syl3anc.3 | |- ( ph -> th ) | ||
| syl3Xanc.4 | |- ( ph -> ta ) | ||
| syl23anc.5 | |- ( ph -> et ) | ||
| syl33anc.6 | |- ( ph -> ze ) | ||
| syl222anc.7 | |- ( ( ( ps /\ ch ) /\ ( th /\ ta ) /\ ( et /\ ze ) ) -> si ) | ||
| Assertion | syl222anc | |- ( ph -> si ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | syl3anc.1 | |- ( ph -> ps ) | |
| 2 | syl3anc.2 | |- ( ph -> ch ) | |
| 3 | syl3anc.3 | |- ( ph -> th ) | |
| 4 | syl3Xanc.4 | |- ( ph -> ta ) | |
| 5 | syl23anc.5 | |- ( ph -> et ) | |
| 6 | syl33anc.6 | |- ( ph -> ze ) | |
| 7 | syl222anc.7 | |- ( ( ( ps /\ ch ) /\ ( th /\ ta ) /\ ( et /\ ze ) ) -> si ) | |
| 8 | 5 6 | jca | |- ( ph -> ( et /\ ze ) ) | 
| 9 | 1 2 3 4 8 7 | syl221anc | |- ( ph -> si ) |