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Theorem nfre1 2551
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 2492 . 2  |-  ( E. x  e.  A  ph  <->  E. x ( x  e.  A  /\  ph )
)
2 nfe1 1520 . 2  |-  F/ x E. x ( x  e.  A  /\  ph )
31, 2nfxfr 1498 1  |-  F/ x E. x  e.  A  ph
Colors of variables: wff set class
Syntax hints:    /\ wa 104   F/wnf 1484   E.wex 1516    e. wcel 2178   E.wrex 2487
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 1471  ax-gen 1473  ax-ie1 1517
This theorem depends on definitions:  df-bi 117  df-nf 1485  df-rex 2492
This theorem is referenced by:  r19.29an  2650  nfiu1  3971  fun11iun  5565  eusvobj2  5953  fodjuomnilemdc  7272  ismkvnex  7283  prarloclem3step  7644  prmuloc2  7715  ltexprlemm  7748  caucvgprprlemaddq  7856  caucvgsrlemgt1  7943  axpre-suploclemres  8049  supinfneg  9751  infsupneg  9752  lbzbi  9772  divalglemeunn  12347  divalglemeuneg  12349  bezoutlemmain  12434  bezout  12447  lss1d  14260  pw1nct  16142  isomninnlem  16171  trirec0  16185  ismkvnnlem  16193
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