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Theorem rexnalim 2483
Description: Relationship between restricted universal and existential quantifiers. In classical logic this would be a biconditional. (Contributed by Jim Kingdon, 17-Aug-2018.)
Assertion
Ref Expression
rexnalim  |-  ( E. x  e.  A  -.  ph 
->  -.  A. x  e.  A  ph )

Proof of Theorem rexnalim
StepHypRef Expression
1 df-rex 2478 . 2  |-  ( E. x  e.  A  -.  ph  <->  E. x ( x  e.  A  /\  -.  ph ) )
2 exanaliim 1658 . . 3  |-  ( E. x ( x  e.  A  /\  -.  ph )  ->  -.  A. x
( x  e.  A  ->  ph ) )
3 df-ral 2477 . . 3  |-  ( A. x  e.  A  ph  <->  A. x
( x  e.  A  ->  ph ) )
42, 3sylnibr 678 . 2  |-  ( E. x ( x  e.  A  /\  -.  ph )  ->  -.  A. x  e.  A  ph )
51, 4sylbi 121 1  |-  ( E. x  e.  A  -.  ph 
->  -.  A. x  e.  A  ph )
Colors of variables: wff set class
Syntax hints:   -. wn 3    -> wi 4    /\ wa 104   A.wal 1362   E.wex 1503    e. wcel 2164   A.wral 2472   E.wrex 2473
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-in1 615  ax-in2 616  ax-5 1458  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-4 1521  ax-17 1537  ax-ial 1545
This theorem depends on definitions:  df-bi 117  df-tru 1367  df-fal 1370  df-nf 1472  df-ral 2477  df-rex 2478
This theorem is referenced by:  nnral  2484  ralexim  2486  iundif2ss  3978  ixp0  6785  omniwomnimkv  7226  alzdvds  11996  pc2dvds  12468  isnsgrp  12989  nninfsellemeq  15504
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