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Theorem rexrab 2818
Description: Existential quantification over a class abstraction. (Contributed by Jeff Madsen, 17-Jun-2011.) (Revised by Mario Carneiro, 3-Sep-2015.)
Hypothesis
Ref Expression
ralab.1  |-  ( y  =  x  ->  ( ph 
<->  ps ) )
Assertion
Ref Expression
rexrab  |-  ( E. x  e.  { y  e.  A  |  ph } ch  <->  E. x  e.  A  ( ps  /\  ch )
)
Distinct variable groups:    x, y    y, A    ps, y
Allowed substitution hints:    ph( x, y)    ps( x)    ch( x, y)    A( x)

Proof of Theorem rexrab
StepHypRef Expression
1 ralab.1 . . . . 5  |-  ( y  =  x  ->  ( ph 
<->  ps ) )
21elrab 2811 . . . 4  |-  ( x  e.  { y  e.  A  |  ph }  <->  ( x  e.  A  /\  ps ) )
32anbi1i 451 . . 3  |-  ( ( x  e.  { y  e.  A  |  ph }  /\  ch )  <->  ( (
x  e.  A  /\  ps )  /\  ch )
)
4 anass 396 . . 3  |-  ( ( ( x  e.  A  /\  ps )  /\  ch ) 
<->  ( x  e.  A  /\  ( ps  /\  ch ) ) )
53, 4bitri 183 . 2  |-  ( ( x  e.  { y  e.  A  |  ph }  /\  ch )  <->  ( x  e.  A  /\  ( ps  /\  ch ) ) )
65rexbii2 2421 1  |-  ( E. x  e.  { y  e.  A  |  ph } ch  <->  E. x  e.  A  ( ps  /\  ch )
)
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 103    <-> wb 104    e. wcel 1463   E.wrex 2392   {crab 2395
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 681  ax-5 1406  ax-7 1407  ax-gen 1408  ax-ie1 1452  ax-ie2 1453  ax-8 1465  ax-10 1466  ax-11 1467  ax-i12 1468  ax-bndl 1469  ax-4 1470  ax-17 1489  ax-i9 1493  ax-ial 1497  ax-i5r 1498  ax-ext 2097
This theorem depends on definitions:  df-bi 116  df-tru 1317  df-nf 1420  df-sb 1719  df-clab 2102  df-cleq 2108  df-clel 2111  df-nfc 2245  df-rex 2397  df-rab 2400  df-v 2660
This theorem is referenced by: (None)
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