Description: Using class abstraction in a context, requiring x and ph disjoint, but based on fewer axioms than wl-clabt . (Contributed by Wolf Lammen, 29-May-2023)
Ref | Expression | ||
---|---|---|---|
Assertion | wl-clabtv |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | biimt | ||
2 | 1 | sbbidv | |
3 | df-clab | ||
4 | df-clab | ||
5 | 2 3 4 | 3bitr4g | |
6 | 5 | eqrdv |