Metamath Proof Explorer


Theorem wuncnv

Description: A weak universe is closed under the converse operator. (Contributed by Mario Carneiro, 2-Jan-2017)

Ref Expression
Hypotheses wun0.1 φUWUni
wunop.2 φAU
Assertion wuncnv φA-1U

Proof

Step Hyp Ref Expression
1 wun0.1 φUWUni
2 wunop.2 φAU
3 1 2 wunrn φranAU
4 1 2 wundm φdomAU
5 1 3 4 wunxp φranA×domAU
6 cnvssrndm A-1ranA×domA
7 6 a1i φA-1ranA×domA
8 1 5 7 wunss φA-1U