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Theorem nfre1 2520
Description:  x is not free in  E. x  e.  A ph. (Contributed by NM, 19-Mar-1997.) (Revised by Mario Carneiro, 7-Oct-2016.)
Assertion
Ref Expression
nfre1  |-  F/ x E. x  e.  A  ph

Proof of Theorem nfre1
StepHypRef Expression
1 df-rex 2461 . 2  |-  ( E. x  e.  A  ph  <->  E. x ( x  e.  A  /\  ph )
)
2 nfe1 1496 . 2  |-  F/ x E. x ( x  e.  A  /\  ph )
31, 2nfxfr 1474 1  |-  F/ x E. x  e.  A  ph
Colors of variables: wff set class
Syntax hints:    /\ wa 104   F/wnf 1460   E.wex 1492    e. wcel 2148   E.wrex 2456
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-5 1447  ax-gen 1449  ax-ie1 1493
This theorem depends on definitions:  df-bi 117  df-nf 1461  df-rex 2461
This theorem is referenced by:  r19.29an  2619  nfiu1  3916  fun11iun  5480  eusvobj2  5857  fodjuomnilemdc  7138  ismkvnex  7149  prarloclem3step  7491  prmuloc2  7562  ltexprlemm  7595  caucvgprprlemaddq  7703  caucvgsrlemgt1  7790  axpre-suploclemres  7896  supinfneg  9590  infsupneg  9591  lbzbi  9611  divalglemeunn  11917  divalglemeuneg  11919  bezoutlemmain  11990  bezout  12003  pw1nct  14603  isomninnlem  14629  trirec0  14643  ismkvnnlem  14651
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