Metamath Proof Explorer


Theorem cnvssrndm

Description: The converse is a subset of the cartesian product of range and domain. (Contributed by Mario Carneiro, 2-Jan-2017)

Ref Expression
Assertion cnvssrndm A -1 ran A × dom A

Proof

Step Hyp Ref Expression
1 relcnv Rel A -1
2 relssdmrn Rel A -1 A -1 dom A -1 × ran A -1
3 1 2 ax-mp A -1 dom A -1 × ran A -1
4 df-rn ran A = dom A -1
5 dfdm4 dom A = ran A -1
6 4 5 xpeq12i ran A × dom A = dom A -1 × ran A -1
7 3 6 sseqtrri A -1 ran A × dom A