Metamath Proof Explorer


Theorem metidss

Description: As a relation, the metric identification is a subset of a Cartesian product. (Contributed by Thierry Arnoux, 7-Feb-2018)

Ref Expression
Assertion metidss
|- ( D e. ( PsMet ` X ) -> ( ~Met ` D ) C_ ( X X. X ) )

Proof

Step Hyp Ref Expression
1 metidval
 |-  ( D e. ( PsMet ` X ) -> ( ~Met ` D ) = { <. x , y >. | ( ( x e. X /\ y e. X ) /\ ( x D y ) = 0 ) } )
2 opabssxp
 |-  { <. x , y >. | ( ( x e. X /\ y e. X ) /\ ( x D y ) = 0 ) } C_ ( X X. X )
3 1 2 eqsstrdi
 |-  ( D e. ( PsMet ` X ) -> ( ~Met ` D ) C_ ( X X. X ) )