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Theorem nfrabxy 2490
Description: A variable not free in a wff remains so in a restricted class abstraction. (Contributed by Jim Kingdon, 19-Jul-2018.)
Hypotheses
Ref Expression
nfrabxy.1  |-  F/ x ph
nfrabxy.2  |-  F/_ x A
Assertion
Ref Expression
nfrabxy  |-  F/_ x { y  e.  A  |  ph }
Distinct variable group:    x, y
Allowed substitution hints:    ph( x, y)    A( x, y)

Proof of Theorem nfrabxy
StepHypRef Expression
1 df-rab 2315 . 2  |-  { y  e.  A  |  ph }  =  { y  |  ( y  e.  A  /\  ph ) }
2 nfrabxy.2 . . . . 5  |-  F/_ x A
32nfcri 2172 . . . 4  |-  F/ x  y  e.  A
4 nfrabxy.1 . . . 4  |-  F/ x ph
53, 4nfan 1457 . . 3  |-  F/ x
( y  e.  A  /\  ph )
65nfab 2182 . 2  |-  F/_ x { y  |  ( y  e.  A  /\  ph ) }
71, 6nfcxfr 2175 1  |-  F/_ x { y  e.  A  |  ph }
Colors of variables: wff set class
Syntax hints:    /\ wa 97   F/wnf 1349    e. wcel 1393   {cab 2026   F/_wnfc 2165   {crab 2310
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-nf 1350  df-sb 1646  df-clab 2027  df-cleq 2033  df-clel 2036  df-nfc 2167  df-rab 2315
This theorem is referenced by:  nfdif  3065  nfin  3143  nfse  4078  mpt2xopoveq  5855  caucvgprprlemaddq  6806
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