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Theorem hbeud 1922
Description: Deduction version of hbeu 1921. (Contributed by NM, 15-Feb-2013.) (Proof rewritten by Jim Kingdon, 25-May-2018.)
Hypotheses
Ref Expression
hbeud.1  |-  ( ph  ->  A. x ph )
hbeud.2  |-  ( ph  ->  A. y ph )
hbeud.3  |-  ( ph  ->  ( ps  ->  A. x ps ) )
Assertion
Ref Expression
hbeud  |-  ( ph  ->  ( E! y ps 
->  A. x E! y ps ) )

Proof of Theorem hbeud
StepHypRef Expression
1 hbeud.2 . . . 4  |-  ( ph  ->  A. y ph )
21nfi 1351 . . 3  |-  F/ y
ph
3 hbeud.1 . . . . 5  |-  ( ph  ->  A. x ph )
43nfi 1351 . . . 4  |-  F/ x ph
5 hbeud.3 . . . 4  |-  ( ph  ->  ( ps  ->  A. x ps ) )
64, 5nfd 1416 . . 3  |-  ( ph  ->  F/ x ps )
72, 6nfeud 1916 . 2  |-  ( ph  ->  F/ x E! y ps )
87nfrd 1413 1  |-  ( ph  ->  ( E! y ps 
->  A. x E! y ps ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4   A.wal 1241   E!weu 1900
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428
This theorem depends on definitions:  df-bi 110  df-tru 1246  df-nf 1350  df-sb 1646  df-eu 1903
This theorem is referenced by: (None)
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