This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
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 |