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Theorem nfccdeq 2987
Description: Variation of nfcdeq 2986 for classes. (Contributed by Mario Carneiro, 11-Aug-2016.)
Hypotheses
Ref Expression
nfccdeq.1  |-  F/_ x A
nfccdeq.2  |- CondEq ( x  =  y  ->  A  =  B )
Assertion
Ref Expression
nfccdeq  |-  A  =  B
Distinct variable groups:    x, B    y, A
Allowed substitution hints:    A( x)    B( y)

Proof of Theorem nfccdeq
Dummy variable  z is distinct from all other variables.
StepHypRef Expression
1 nfccdeq.1 . . . 4  |-  F/_ x A
21nfcri 2333 . . 3  |-  F/ x  z  e.  A
3 equid 1715 . . . . 5  |-  z  =  z
43cdeqth 2976 . . . 4  |- CondEq ( x  =  y  ->  z  =  z )
5 nfccdeq.2 . . . 4  |- CondEq ( x  =  y  ->  A  =  B )
64, 5cdeqel 2985 . . 3  |- CondEq ( x  =  y  ->  (
z  e.  A  <->  z  e.  B ) )
72, 6nfcdeq 2986 . 2  |-  ( z  e.  A  <->  z  e.  B )
87eqriv 2193 1  |-  A  =  B
Colors of variables: wff set class
Syntax hints:    = wceq 1364    e. wcel 2167   F/_wnfc 2326  CondEqwcdeq 2972
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 710  ax-5 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-10 1519  ax-11 1520  ax-i12 1521  ax-bndl 1523  ax-4 1524  ax-17 1540  ax-i9 1544  ax-ial 1548  ax-i5r 1549  ax-ext 2178
This theorem depends on definitions:  df-bi 117  df-nf 1475  df-sb 1777  df-cleq 2189  df-clel 2192  df-nfc 2328  df-cdeq 2973
This theorem is referenced by: (None)
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