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Theorem csbie2g 3109
Description: Conversion of implicit substitution to explicit class substitution. This version of sbcie 2999 avoids a disjointness condition on  x and  A by substituting twice. (Contributed by Mario Carneiro, 11-Nov-2016.)
Hypotheses
Ref Expression
csbie2g.1  |-  ( x  =  y  ->  B  =  C )
csbie2g.2  |-  ( y  =  A  ->  C  =  D )
Assertion
Ref Expression
csbie2g  |-  ( A  e.  V  ->  [_ A  /  x ]_ B  =  D )
Distinct variable groups:    x, y    y, A    y, B    x, C    y, D
Allowed substitution hints:    A( x)    B( x)    C( y)    D( x)    V( x, y)

Proof of Theorem csbie2g
Dummy variable  z is distinct from all other variables.
StepHypRef Expression
1 df-csb 3060 . 2  |-  [_ A  /  x ]_ B  =  { z  |  [. A  /  x ]. z  e.  B }
2 csbie2g.1 . . . . 5  |-  ( x  =  y  ->  B  =  C )
32eleq2d 2247 . . . 4  |-  ( x  =  y  ->  (
z  e.  B  <->  z  e.  C ) )
4 csbie2g.2 . . . . 5  |-  ( y  =  A  ->  C  =  D )
54eleq2d 2247 . . . 4  |-  ( y  =  A  ->  (
z  e.  C  <->  z  e.  D ) )
63, 5sbcie2g 2998 . . 3  |-  ( A  e.  V  ->  ( [. A  /  x ]. z  e.  B  <->  z  e.  D ) )
76abbi1dv 2297 . 2  |-  ( A  e.  V  ->  { z  |  [. A  /  x ]. z  e.  B }  =  D )
81, 7eqtrid 2222 1  |-  ( A  e.  V  ->  [_ A  /  x ]_ B  =  D )
Colors of variables: wff set class
Syntax hints:    -> wi 4    = wceq 1353    e. wcel 2148   {cab 2163   [.wsbc 2964   [_csb 3059
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 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-ext 2159
This theorem depends on definitions:  df-bi 117  df-tru 1356  df-nf 1461  df-sb 1763  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-v 2741  df-sbc 2965  df-csb 3060
This theorem is referenced by: (None)
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