Description: Equality theorem for unordered triples. (Contributed by NM, 22-Jun-2014)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | tpeq1d.1 | |- ( ph -> A = B ) |
|
| tpeq123d.2 | |- ( ph -> C = D ) |
||
| tpeq123d.3 | |- ( ph -> E = F ) |
||
| Assertion | tpeq123d | |- ( ph -> { A , C , E } = { B , D , F } ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | tpeq1d.1 | |- ( ph -> A = B ) |
|
| 2 | tpeq123d.2 | |- ( ph -> C = D ) |
|
| 3 | tpeq123d.3 | |- ( ph -> E = F ) |
|
| 4 | 1 | tpeq1d | |- ( ph -> { A , C , E } = { B , C , E } ) |
| 5 | 2 | tpeq2d | |- ( ph -> { B , C , E } = { B , D , E } ) |
| 6 | 3 | tpeq3d | |- ( ph -> { B , D , E } = { B , D , F } ) |
| 7 | 4 5 6 | 3eqtrd | |- ( ph -> { A , C , E } = { B , D , F } ) |