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Theorem rexnalim 2539
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 2534 . 2  |-  ( E. x  e.  A  -.  ph  <->  E. x ( x  e.  A  /\  -.  ph ) )
2 exanaliim 1700 . . 3  |-  ( E. x ( x  e.  A  /\  -.  ph )  ->  -.  A. x
( x  e.  A  ->  ph ) )
3 df-ral 2533 . . 3  |-  ( A. x  e.  A  ph  <->  A. x
( x  e.  A  ->  ph ) )
42, 3sylnibr 688 . 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 1400   E.wex 1545    e. wcel 2209   A.wral 2528   E.wrex 2529
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 623  ax-in2 624  ax-5 1500  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-4 1563  ax-17 1579  ax-ial 1587
This theorem depends on definitions:  df-bi 117  df-tru 1405  df-fal 1408  df-nf 1514  df-ral 2533  df-rex 2534
This theorem is referenced by:  nnral  2540  ralexim  2542  rexanaliim  2656  iundif2ss  4073  ixp0  7003  omniwomnimkv  7497  alzdvds  12599  pc2dvds  13087  ballotfilem4  13219  isnsgrp  13698  umgr2edg1  16364  umgr2edgneu  16367  nninfsellemeq  16962
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