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Theorem metrel 12500
Description: The class of metrics is a relation. (Contributed by Jim Kingdon, 20-Apr-2023.)
Assertion
Ref Expression
metrel  |-  Rel  Met

Proof of Theorem metrel
Dummy variables  e  d  x  y  z are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 mptrel 4662 . 2  |-  Rel  (
e  e.  _V  |->  { d  e.  ( RR 
^m  ( e  X.  e ) )  | 
A. x  e.  e 
A. y  e.  e  ( ( ( x d y )  =  0  <->  x  =  y
)  /\  A. z  e.  e  ( x
d y )  <_ 
( ( z d x )  +  ( z d y ) ) ) } )
2 df-met 12147 . . 3  |-  Met  =  ( e  e.  _V  |->  { d  e.  ( RR  ^m  ( e  X.  e ) )  |  A. x  e.  e  A. y  e.  e  ( ( ( x d y )  =  0  <->  x  =  y )  /\  A. z  e.  e  (
x d y )  <_  ( ( z d x )  +  ( z d y ) ) ) } )
32releqi 4617 . 2  |-  ( Rel 
Met 
<->  Rel  ( e  e. 
_V  |->  { d  e.  ( RR  ^m  (
e  X.  e ) )  |  A. x  e.  e  A. y  e.  e  ( (
( x d y )  =  0  <->  x  =  y )  /\  A. z  e.  e  ( x d y )  <_  ( ( z d x )  +  ( z d y ) ) ) } ) )
41, 3mpbir 145 1  |-  Rel  Met
Colors of variables: wff set class
Syntax hints:    /\ wa 103    <-> wb 104    = wceq 1331   A.wral 2414   {crab 2418   _Vcvv 2681   class class class wbr 3924    |-> cmpt 3984    X. cxp 4532   Rel wrel 4539  (class class class)co 5767    ^m cmap 6535   RRcr 7612   0cc0 7613    + caddc 7616    <_ cle 7794   Metcmet 12139
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 698  ax-5 1423  ax-7 1424  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-10 1483  ax-11 1484  ax-i12 1485  ax-bndl 1486  ax-4 1487  ax-14 1492  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2119  ax-sep 4041  ax-pow 4093  ax-pr 4126
This theorem depends on definitions:  df-bi 116  df-3an 964  df-tru 1334  df-nf 1437  df-sb 1736  df-clab 2124  df-cleq 2130  df-clel 2133  df-nfc 2268  df-ral 2419  df-rex 2420  df-v 2683  df-un 3070  df-in 3072  df-ss 3079  df-pw 3507  df-sn 3528  df-pr 3529  df-op 3531  df-opab 3985  df-mpt 3986  df-xp 4540  df-rel 4541  df-met 12147
This theorem is referenced by:  metflem  12507  ismet2  12512
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