Description: An operation maps to a class to which all values belong. (Contributed by NM, 7-Feb-2004)
Ref | Expression | ||
---|---|---|---|
Assertion | ffnov | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ffnfv | |
|
2 | fveq2 | |
|
3 | df-ov | |
|
4 | 2 3 | eqtr4di | |
5 | 4 | eleq1d | |
6 | 5 | ralxp | |
7 | 6 | anbi2i | |
8 | 1 7 | bitri | |