Metamath Proof Explorer


Theorem relcnv

Description: A converse is a relation. Theorem 12 of Suppes p. 62. (Contributed by NM, 29-Oct-1996)

Ref Expression
Assertion relcnv RelA-1

Proof

Step Hyp Ref Expression
1 df-cnv A-1=xy|yAx
2 1 relopabiv RelA-1