Metamath Proof Explorer


Theorem rele

Description: The membership relation is a relation. (Contributed by NM, 26-Apr-1998) (Revised by Mario Carneiro, 21-Dec-2013)

Ref Expression
Assertion rele Rel E

Proof

Step Hyp Ref Expression
1 df-eprel E = x y | x y
2 1 relopabiv Rel E