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Theorem metrel 15010
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 4849 . 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 14503 . . 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 4801 . 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 146 1  |-  Rel  Met
Colors of variables: wff set class
Syntax hints:    /\ wa 104    <-> wb 105    = wceq 1395   A.wral 2508   {crab 2512   _Vcvv 2799   class class class wbr 4082    |-> cmpt 4144    X. cxp 4716   Rel wrel 4723  (class class class)co 6000    ^m cmap 6793   RRcr 7994   0cc0 7995    + caddc 7998    <_ cle 8178   Metcmet 14495
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-14 2203  ax-ext 2211  ax-sep 4201  ax-pow 4257  ax-pr 4292
This theorem depends on definitions:  df-bi 117  df-3an 1004  df-tru 1398  df-nf 1507  df-sb 1809  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ral 2513  df-rex 2514  df-v 2801  df-un 3201  df-in 3203  df-ss 3210  df-pw 3651  df-sn 3672  df-pr 3673  df-op 3675  df-opab 4145  df-mpt 4146  df-xp 4724  df-rel 4725  df-met 14503
This theorem is referenced by:  metflem  15017  ismet2  15022
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