Metamath Proof Explorer


Theorem dfv2

Description: Alternate definition of the universal class (see df-v ). (Contributed by BJ, 30-Nov-2019)

Ref Expression
Assertion dfv2 V=x|

Proof

Step Hyp Ref Expression
1 df-v V=x|x=x
2 equid x=x
3 2 bitru x=x
4 3 abbii x|x=x=x|
5 1 4 eqtri V=x|