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Theorem clabel 2304
Description: Membership of a class abstraction in another class. (Contributed by NM, 17-Jan-2006.)
Assertion
Ref Expression
clabel  |-  ( { x  |  ph }  e.  A  <->  E. y ( y  e.  A  /\  A. x ( x  e.  y  <->  ph ) ) )
Distinct variable groups:    y, A    ph, y    x, y
Allowed substitution hints:    ph( x)    A( x)

Proof of Theorem clabel
StepHypRef Expression
1 df-clel 2173 . 2  |-  ( { x  |  ph }  e.  A  <->  E. y ( y  =  { x  | 
ph }  /\  y  e.  A ) )
2 abeq2 2286 . . . 4  |-  ( y  =  { x  | 
ph }  <->  A. x
( x  e.  y  <->  ph ) )
32anbi2ci 459 . . 3  |-  ( ( y  =  { x  |  ph }  /\  y  e.  A )  <->  ( y  e.  A  /\  A. x
( x  e.  y  <->  ph ) ) )
43exbii 1605 . 2  |-  ( E. y ( y  =  { x  |  ph }  /\  y  e.  A
)  <->  E. y ( y  e.  A  /\  A. x ( x  e.  y  <->  ph ) ) )
51, 4bitri 184 1  |-  ( { x  |  ph }  e.  A  <->  E. y ( y  e.  A  /\  A. x ( x  e.  y  <->  ph ) ) )
Colors of variables: wff set class
Syntax hints:    /\ wa 104    <-> wb 105   A.wal 1351    = wceq 1353   E.wex 1492    e. wcel 2148   {cab 2163
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-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-11 1506  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-ext 2159
This theorem depends on definitions:  df-bi 117  df-nf 1461  df-sb 1763  df-clab 2164  df-cleq 2170  df-clel 2173
This theorem is referenced by:  frecabcl  6396
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