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Theorem euabex 4203
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 3645 . 2  |-  ( E! x ph  <->  E. y { x  |  ph }  =  { y } )
2 vex 2729 . . . . 5  |-  y  e. 
_V
32snex 4164 . . . 4  |-  { y }  e.  _V
4 eleq1 2229 . . . 4  |-  ( { x  |  ph }  =  { y }  ->  ( { x  |  ph }  e.  _V  <->  { y }  e.  _V )
)
53, 4mpbiri 167 . . 3  |-  ( { x  |  ph }  =  { y }  ->  { x  |  ph }  e.  _V )
65exlimiv 1586 . 2  |-  ( E. y { x  | 
ph }  =  {
y }  ->  { x  |  ph }  e.  _V )
71, 6sylbi 120 1  |-  ( E! x ph  ->  { x  |  ph }  e.  _V )
Colors of variables: wff set class
Syntax hints:    -> wi 4    = wceq 1343   E.wex 1480   E!weu 2014    e. wcel 2136   {cab 2151   _Vcvv 2726   {csn 3576
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-14 2139  ax-ext 2147  ax-sep 4100  ax-pow 4153
This theorem depends on definitions:  df-bi 116  df-tru 1346  df-nf 1449  df-sb 1751  df-eu 2017  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-v 2728  df-in 3122  df-ss 3129  df-pw 3561  df-sn 3582
This theorem is referenced by: (None)
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