Description: Alternate definition of the function relation predicate, cf. dfdisjALTV2 . (Contributed by Peter Mazsa, 8-Feb-2018)
Ref | Expression | ||
---|---|---|---|
Assertion | dffunALTV2 | |- ( FunALTV F <-> ( ,~ F C_ _I /\ Rel F ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-funALTV | |- ( FunALTV F <-> ( CnvRefRel ,~ F /\ Rel F ) ) |
|
2 | cnvrefrelcoss2 | |- ( CnvRefRel ,~ F <-> ,~ F C_ _I ) |
|
3 | 2 | anbi1i | |- ( ( CnvRefRel ,~ F /\ Rel F ) <-> ( ,~ F C_ _I /\ Rel F ) ) |
4 | 1 3 | bitri | |- ( FunALTV F <-> ( ,~ F C_ _I /\ Rel F ) ) |