Theorem abexex 6211

Description: A condition where a class builder continues to exist after its wff is existentially quantified. (Contributed by NM, 4-Mar-2007.)

Hypotheses

Ref	Expression
abexex.1	|- A e. _V
abexex.2	|- ( ph -> x e. A )
abexex.3	|- { y | ph } e. _V

Assertion

Ref	Expression
abexex	|- { y | E. x ph } e. _V

Distinct variable group:   x, y, A

Allowed substitution hints:   ph( x, y)

Proof of Theorem abexex

Step	Hyp	Ref	Expression
1		df-rex 2490	. . . 4 |- ( E. x e. A ph <-> E. x ( x e. A /\ ph ) )
2		abexex.2	. . . . . 6 |- ( ph -> x e. A )
3	2	pm4.71ri 392	. . . . 5 |- ( ph <-> ( x e. A /\ ph ) )
4	3	exbii 1628	. . . 4 |- ( E. x ph <-> E. x ( x e. A /\ ph ) )
5	1, 4	bitr4i 187	. . 3 |- ( E. x e. A ph <-> E. x ph )
6	5	abbii 2321	. 2 |- { y | E. x e. A ph } = { y | E. x ph }
7		abexex.1	. . 3 |- A e. _V
8		abexex.3	. . 3 |- { y | ph } e. _V
9	7, 8	abrexex2 6209	. 2 |- { y | E. x e. A ph } e. _V
10	6, 9	eqeltrri 2279	1 |- { y | E. x ph } e. _V

Syntax hints:   -> wi 4   /\ wa 104   E.wex 1515   e. wcel 2176   {cab 2191   E.wrex 2485   _Vcvv 2772

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 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-13 2178  ax-14 2179  ax-ext 2187  ax-coll 4159  ax-sep 4162  ax-pow 4218  ax-pr 4253  ax-un 4480

This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-nf 1484  df-sb 1786  df-eu 2057  df-mo 2058  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-ral 2489  df-rex 2490  df-reu 2491  df-rab 2493  df-v 2774  df-sbc 2999  df-csb 3094  df-un 3170  df-in 3172  df-ss 3179  df-pw 3618  df-sn 3639  df-pr 3640  df-op 3642  df-uni 3851  df-iun 3929  df-br 4045  df-opab 4106  df-mpt 4107  df-id 4340  df-xp 4681  df-rel 4682  df-cnv 4683  df-co 4684  df-dm 4685  df-rn 4686  df-res 4687  df-ima 4688  df-iota 5232  df-fun 5273  df-fn 5274  df-f 5275  df-f1 5276  df-fo 5277  df-f1o 5278  df-fv 5279

This theorem is referenced by: (None)