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Theorem isoeq4 5464
Description: Equality theorem for isomorphisms. (Contributed by NM, 17-May-2004.)
Assertion
Ref Expression
isoeq4  |-  ( A  =  C  ->  ( H  Isom  R ,  S  ( A ,  B )  <-> 
H  Isom  R ,  S  ( C ,  B ) ) )

Proof of Theorem isoeq4
Dummy variables  x  y are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 f1oeq2 5138 . . 3  |-  ( A  =  C  ->  ( H : A -1-1-onto-> B  <->  H : C -1-1-onto-> B ) )
2 raleq 2549 . . . 4  |-  ( A  =  C  ->  ( A. y  e.  A  ( x R y  <-> 
( H `  x
) S ( H `
 y ) )  <->  A. y  e.  C  ( x R y  <-> 
( H `  x
) S ( H `
 y ) ) ) )
32raleqbi1dv 2557 . . 3  |-  ( A  =  C  ->  ( A. x  e.  A  A. y  e.  A  ( x R y  <-> 
( H `  x
) S ( H `
 y ) )  <->  A. x  e.  C  A. y  e.  C  ( x R y  <-> 
( H `  x
) S ( H `
 y ) ) ) )
41, 3anbi12d 456 . 2  |-  ( A  =  C  ->  (
( H : A -1-1-onto-> B  /\  A. x  e.  A  A. y  e.  A  ( x R y  <-> 
( H `  x
) S ( H `
 y ) ) )  <->  ( H : C
-1-1-onto-> B  /\  A. x  e.  C  A. y  e.  C  ( x R y  <->  ( H `  x ) S ( H `  y ) ) ) ) )
5 df-isom 4931 . 2  |-  ( H 
Isom  R ,  S  ( A ,  B )  <-> 
( H : A -1-1-onto-> B  /\  A. x  e.  A  A. y  e.  A  ( x R y  <-> 
( H `  x
) S ( H `
 y ) ) ) )
6 df-isom 4931 . 2  |-  ( H 
Isom  R ,  S  ( C ,  B )  <-> 
( H : C -1-1-onto-> B  /\  A. x  e.  C  A. y  e.  C  ( x R y  <-> 
( H `  x
) S ( H `
 y ) ) ) )
74, 5, 63bitr4g 221 1  |-  ( A  =  C  ->  ( H  Isom  R ,  S  ( A ,  B )  <-> 
H  Isom  R ,  S  ( C ,  B ) ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 102    <-> wb 103    = wceq 1284   A.wral 2348   class class class wbr 3785   -1-1-onto->wf1o 4921   ` cfv 4922    Isom wiso 4923
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-io 662  ax-5 1376  ax-7 1377  ax-gen 1378  ax-ie1 1422  ax-ie2 1423  ax-8 1435  ax-10 1436  ax-11 1437  ax-i12 1438  ax-bndl 1439  ax-4 1440  ax-17 1459  ax-i9 1463  ax-ial 1467  ax-i5r 1468  ax-ext 2063
This theorem depends on definitions:  df-bi 115  df-tru 1287  df-nf 1390  df-sb 1686  df-cleq 2074  df-clel 2077  df-nfc 2208  df-ral 2353  df-fn 4925  df-f 4926  df-f1 4927  df-fo 4928  df-f1o 4929  df-isom 4931
This theorem is referenced by: (None)
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