Description: The domain and range of a one-to-one, onto function are equinumerous. (Contributed by NM, 19-Jun-1998)
Ref | Expression | ||
---|---|---|---|
Hypothesis | f1oen.1 | |
|
Assertion | f1oen | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | f1oen.1 | |
|
2 | f1oeng | |
|
3 | 1 2 | mpan | |