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Theorem eqsbc3r 2819
Description: eqsbc3 2802 with setvar variable on right side of equals sign. (Contributed by Alan Sare, 24-Oct-2011.)
Assertion
Ref Expression
eqsbc3r  |-  ( A  e.  B  ->  ( [. A  /  x ]. C  =  x  <->  C  =  A ) )
Distinct variable groups:    x, C    x, A
Allowed substitution hint:    B( x)

Proof of Theorem eqsbc3r
StepHypRef Expression
1 eqcom 2042 . . . . . 6  |-  ( C  =  x  <->  x  =  C )
21sbcbii 2818 . . . . 5  |-  ( [. A  /  x ]. C  =  x  <->  [. A  /  x ]. x  =  C
)
32biimpi 113 . . . 4  |-  ( [. A  /  x ]. C  =  x  ->  [. A  /  x ]. x  =  C )
4 eqsbc3 2802 . . . 4  |-  ( A  e.  B  ->  ( [. A  /  x ]. x  =  C  <->  A  =  C ) )
53, 4syl5ib 143 . . 3  |-  ( A  e.  B  ->  ( [. A  /  x ]. C  =  x  ->  A  =  C ) )
6 eqcom 2042 . . 3  |-  ( A  =  C  <->  C  =  A )
75, 6syl6ib 150 . 2  |-  ( A  e.  B  ->  ( [. A  /  x ]. C  =  x  ->  C  =  A ) )
8 idd 21 . . . . 5  |-  ( A  e.  B  ->  ( C  =  A  ->  C  =  A ) )
98, 6syl6ibr 151 . . . 4  |-  ( A  e.  B  ->  ( C  =  A  ->  A  =  C ) )
109, 4sylibrd 158 . . 3  |-  ( A  e.  B  ->  ( C  =  A  ->  [. A  /  x ]. x  =  C )
)
1110, 2syl6ibr 151 . 2  |-  ( A  e.  B  ->  ( C  =  A  ->  [. A  /  x ]. C  =  x )
)
127, 11impbid 120 1  |-  ( A  e.  B  ->  ( [. A  /  x ]. C  =  x  <->  C  =  A ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 98    = wceq 1243    e. wcel 1393   [.wsbc 2764
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022
This theorem depends on definitions:  df-bi 110  df-tru 1246  df-nf 1350  df-sb 1646  df-clab 2027  df-cleq 2033  df-clel 2036  df-nfc 2167  df-v 2559  df-sbc 2765
This theorem is referenced by: (None)
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