Description: Deduction joining 3 implications to form implication of conjunctions. (Contributed by NM, 24-Feb-2005)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | 3anim123d.1 | |- ( ph -> ( ps -> ch ) ) |
|
| 3anim123d.2 | |- ( ph -> ( th -> ta ) ) |
||
| 3anim123d.3 | |- ( ph -> ( et -> ze ) ) |
||
| Assertion | 3anim123d | |- ( ph -> ( ( ps /\ th /\ et ) -> ( ch /\ ta /\ ze ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 3anim123d.1 | |- ( ph -> ( ps -> ch ) ) |
|
| 2 | 3anim123d.2 | |- ( ph -> ( th -> ta ) ) |
|
| 3 | 3anim123d.3 | |- ( ph -> ( et -> ze ) ) |
|
| 4 | 1 2 | anim12d | |- ( ph -> ( ( ps /\ th ) -> ( ch /\ ta ) ) ) |
| 5 | 4 3 | anim12d | |- ( ph -> ( ( ( ps /\ th ) /\ et ) -> ( ( ch /\ ta ) /\ ze ) ) ) |
| 6 | df-3an | |- ( ( ps /\ th /\ et ) <-> ( ( ps /\ th ) /\ et ) ) |
|
| 7 | df-3an | |- ( ( ch /\ ta /\ ze ) <-> ( ( ch /\ ta ) /\ ze ) ) |
|
| 8 | 5 6 7 | 3imtr4g | |- ( ph -> ( ( ps /\ th /\ et ) -> ( ch /\ ta /\ ze ) ) ) |