Description: Deduction joining 3 implications to form implication of conjunctions. (Contributed by NM, 24-Feb-2005)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | 3anim123d.1 | ||
| 3anim123d.2 | |||
| 3anim123d.3 | |||
| Assertion | 3anim123d |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 3anim123d.1 | ||
| 2 | 3anim123d.2 | ||
| 3 | 3anim123d.3 | ||
| 4 | 1 2 | anim12d | |
| 5 | 4 3 | anim12d | |
| 6 | df-3an | ||
| 7 | df-3an | ||
| 8 | 5 6 7 | 3imtr4g |