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Description: The range of the empty set is empty. Part of Theorem 3.8(v) of Monk1 p. 36. (Contributed by NM, 4-Jul-1994)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | rn0 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | dm0 | ||
| 2 | dm0rn0 | ||
| 3 | 1 2 | mpbi |