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Theorem nfre1 2474
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 2420 . 2  |-  ( E. x  e.  A  ph  <->  E. x ( x  e.  A  /\  ph )
)
2 nfe1 1472 . 2  |-  F/ x E. x ( x  e.  A  /\  ph )
31, 2nfxfr 1450 1  |-  F/ x E. x  e.  A  ph
Colors of variables: wff set class
Syntax hints:    /\ wa 103   F/wnf 1436   E.wex 1468    e. wcel 1480   E.wrex 2415
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1423  ax-gen 1425  ax-ie1 1469
This theorem depends on definitions:  df-bi 116  df-nf 1437  df-rex 2420
This theorem is referenced by:  r19.29an  2572  nfiu1  3838  fun11iun  5381  eusvobj2  5753  fodjuomnilemdc  7009  ismkvnex  7022  prarloclem3step  7297  prmuloc2  7368  ltexprlemm  7401  caucvgprprlemaddq  7509  caucvgsrlemgt1  7596  axpre-suploclemres  7702  supinfneg  9383  infsupneg  9384  lbzbi  9401  divalglemeunn  11607  divalglemeuneg  11609  bezoutlemmain  11675  bezout  11688  isomninnlem  13214
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