Description: The range of a Cartesian product. Part of Theorem 3.13(x) of Monk1 p. 37. (Contributed by NM, 12-Apr-2004)
Ref | Expression | ||
---|---|---|---|
Assertion | rnxp | |- ( A =/= (/) -> ran ( A X. B ) = B ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-rn | |- ran ( A X. B ) = dom `' ( A X. B ) |
|
2 | cnvxp | |- `' ( A X. B ) = ( B X. A ) |
|
3 | 2 | dmeqi | |- dom `' ( A X. B ) = dom ( B X. A ) |
4 | 1 3 | eqtri | |- ran ( A X. B ) = dom ( B X. A ) |
5 | dmxp | |- ( A =/= (/) -> dom ( B X. A ) = B ) |
|
6 | 4 5 | eqtrid | |- ( A =/= (/) -> ran ( A X. B ) = B ) |