Metamath Proof Explorer


Theorem numth3

Description: All sets are well-orderable under choice. (Contributed by Stefan O'Rear, 28-Feb-2015)

Ref Expression
Assertion numth3 A V A dom card

Proof

Step Hyp Ref Expression
1 elex A V A V
2 cardeqv dom card = V
3 1 2 eleqtrrdi A V A dom card