Description: Alternate definition of the universal class (see df-v ). (Contributed by BJ, 30-Nov-2019)
Ref | Expression | ||
---|---|---|---|
Assertion | dfv2 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-v | |
|
2 | equid | |
|
3 | 2 | bitru | |
4 | 3 | abbii | |
5 | 1 4 | eqtri | |