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Theorem euabex 4311
Description: The abstraction of a wff with existential uniqueness exists. (Contributed by NM, 25-Nov-1994.)
Assertion
Ref Expression
euabex  |-  ( E! x ph  ->  { x  |  ph }  e.  _V )

Proof of Theorem euabex
Dummy variable  y is distinct from all other variables.
StepHypRef Expression
1 euabsn2 3735 . 2  |-  ( E! x ph  <->  E. y { x  |  ph }  =  { y } )
2 vex 2802 . . . . 5  |-  y  e. 
_V
32snex 4269 . . . 4  |-  { y }  e.  _V
4 eleq1 2292 . . . 4  |-  ( { x  |  ph }  =  { y }  ->  ( { x  |  ph }  e.  _V  <->  { y }  e.  _V )
)
53, 4mpbiri 168 . . 3  |-  ( { x  |  ph }  =  { y }  ->  { x  |  ph }  e.  _V )
65exlimiv 1644 . 2  |-  ( E. y { x  | 
ph }  =  {
y }  ->  { x  |  ph }  e.  _V )
71, 6sylbi 121 1  |-  ( E! x ph  ->  { x  |  ph }  e.  _V )
Colors of variables: wff set class
Syntax hints:    -> wi 4    = wceq 1395   E.wex 1538   E!weu 2077    e. wcel 2200   {cab 2215   _Vcvv 2799   {csn 3666
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-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-14 2203  ax-ext 2211  ax-sep 4202  ax-pow 4258
This theorem depends on definitions:  df-bi 117  df-tru 1398  df-nf 1507  df-sb 1809  df-eu 2080  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-v 2801  df-in 3203  df-ss 3210  df-pw 3651  df-sn 3672
This theorem is referenced by: (None)
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