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Description: The Bigcup relationship is a relationship. (Contributed by Scott Fenton, 11-Apr-2012)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | relbigcup |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | relxp | ||
| 2 | reldif | ||
| 3 | 1 2 | ax-mp | |
| 4 | df-bigcup | ||
| 5 | 4 | releqi | |
| 6 | 3 5 | mpbir |