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Theorem elcnv2 4933
Description: Membership in a converse. Equation 5 of [Suppes] p. 62. (Contributed by NM, 11-Aug-2004.)
Assertion
Ref Expression
elcnv2  |-  ( A  e.  `' R  <->  E. x E. y ( A  = 
<. x ,  y >.  /\  <. y ,  x >.  e.  R ) )
Distinct variable groups:    x, y, A   
x, R, y

Proof of Theorem elcnv2
StepHypRef Expression
1 elcnv 4932 . 2  |-  ( A  e.  `' R  <->  E. x E. y ( A  = 
<. x ,  y >.  /\  y R x ) )
2 df-br 4110 . . . 4  |-  ( y R x  <->  <. y ,  x >.  e.  R
)
32anbi2i 457 . . 3  |-  ( ( A  =  <. x ,  y >.  /\  y R x )  <->  ( A  =  <. x ,  y
>.  /\  <. y ,  x >.  e.  R ) )
432exbii 1655 . 2  |-  ( E. x E. y ( A  =  <. x ,  y >.  /\  y R x )  <->  E. x E. y ( A  = 
<. x ,  y >.  /\  <. y ,  x >.  e.  R ) )
51, 4bitri 184 1  |-  ( A  e.  `' R  <->  E. x E. y ( A  = 
<. x ,  y >.  /\  <. y ,  x >.  e.  R ) )
Colors of variables: wff set class
Syntax hints:    /\ wa 104    <-> wb 105    = wceq 1398   E.wex 1541    e. wcel 2203   <.cop 3692   class class class wbr 4109   `'ccnv 4748
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 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-14 2206  ax-ext 2214  ax-sep 4228  ax-pow 4287  ax-pr 4322
This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1812  df-clab 2219  df-cleq 2225  df-clel 2228  df-nfc 2373  df-v 2815  df-un 3215  df-in 3217  df-ss 3224  df-pw 3671  df-sn 3695  df-pr 3696  df-op 3698  df-br 4110  df-opab 4172  df-cnv 4757
This theorem is referenced by:  cnvuni  4941
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