Description: Equality theorem for unordered triples. (Contributed by NM, 22-Jun-2014)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | tpeq1d.1 | ||
| tpeq123d.2 | |||
| tpeq123d.3 | |||
| Assertion | tpeq123d |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | tpeq1d.1 | ||
| 2 | tpeq123d.2 | ||
| 3 | tpeq123d.3 | ||
| 4 | 1 | tpeq1d | |
| 5 | 2 | tpeq2d | |
| 6 | 3 | tpeq3d | |
| 7 | 4 5 6 | 3eqtrd |