Metamath Proof Explorer


Theorem brne0

Description: If two sets are in a binary relation, the relation cannot be empty. (Contributed by Alexander van der Vekens, 7-Jul-2018)

Ref Expression
Assertion brne0 A R B R

Proof

Step Hyp Ref Expression
1 df-br A R B A B R
2 ne0i A B R R
3 1 2 sylbi A R B R