Theorem elvvv 4917

Description: Membership in universal class of ordered triples. (Contributed by NM, 17-Dec-2008.)

Assertion

Ref	Expression
elvvv	|- ( A e. ( ( _V X. _V ) X. _V ) <-> E. x E. y E. z A = <. <. x , y >. , z >. )

Distinct variable group:   x, y, z, A

Proof of Theorem elvvv

Dummy variable w is distinct from all other variables.

Step	Hyp	Ref	Expression
1		elxp 4876	. 2 |- ( A e. ( ( _V X. _V ) X. _V ) <-> E. w E. z ( A = <. w , z >. /\ ( w e. ( _V X. _V ) /\ z e. _V ) ) )
2		anass 649	. . . . 5 |- ( ( ( A = <. w , z >. /\ w e. ( _V X. _V ) ) /\ z e. _V ) <-> ( A = <. w , z >. /\ ( w e. ( _V X. _V ) /\ z e. _V ) ) )
3		19.42vv 1926	. . . . . 6 |- ( E. x E. y ( A = <. w , z >. /\ w = <. x , y >. ) <-> ( A = <. w , z >. /\ E. x E. y w = <. x , y >. ) )
4		ancom 450	. . . . . . 7 |- ( ( w = <. x , y >. /\ A = <. w , z >. ) <-> ( A = <. w , z >. /\ w = <. x , y >. ) )
5	4	2exbii 1635	. . . . . 6 |- ( E. x E. y ( w = <. x , y >. /\ A = <. w , z >. ) <-> E. x E. y ( A = <. w , z >. /\ w = <. x , y >. ) )
6		vex 2994	. . . . . . . 8 |- z e. _V
7	6	biantru 505	. . . . . . 7 |- ( ( A = <. w , z >. /\ w e. ( _V X. _V ) ) <-> ( ( A = <. w , z >. /\ w e. ( _V X. _V ) ) /\ z e. _V ) )
8		elvv 4916	. . . . . . . 8 |- ( w e. ( _V X. _V ) <-> E. x E. y w = <. x , y >. )
9	8	anbi2i 694	. . . . . . 7 |- ( ( A = <. w , z >. /\ w e. ( _V X. _V ) ) <-> ( A = <. w , z >. /\ E. x E. y w = <. x , y >. ) )
10	7, 9	bitr3i 251	. . . . . 6 |- ( ( ( A = <. w , z >. /\ w e. ( _V X. _V ) ) /\ z e. _V ) <-> ( A = <. w , z >. /\ E. x E. y w = <. x , y >. ) )
11	3, 5, 10	3bitr4ri 278	. . . . 5 |- ( ( ( A = <. w , z >. /\ w e. ( _V X. _V ) ) /\ z e. _V ) <-> E. x E. y ( w = <. x , y >. /\ A = <. w , z >. ) )
12	2, 11	bitr3i 251	. . . 4 |- ( ( A = <. w , z >. /\ ( w e. ( _V X. _V ) /\ z e. _V ) ) <-> E. x E. y ( w = <. x , y >. /\ A = <. w , z >. ) )
13	12	2exbii 1635	. . 3 |- ( E. w E. z ( A = <. w , z >. /\ ( w e. ( _V X. _V ) /\ z e. _V ) ) <-> E. w E. z E. x E. y ( w = <. x , y >. /\ A = <. w , z >. ) )
14		exrot4 1791	. . . 4 |- ( E. x E. y E. w E. z ( w = <. x , y >. /\ A = <. w , z >. ) <-> E. w E. z E. x E. y ( w = <. x , y >. /\ A = <. w , z >. ) )
15		excom 1787	. . . . . 6 |- ( E. w E. z ( w = <. x , y >. /\ A = <. w , z >. ) <-> E. z E. w ( w = <. x , y >. /\ A = <. w , z >. ) )
16		opex 4575	. . . . . . . 8 |- <. x , y >. e. _V
17		opeq1 4078	. . . . . . . . 9 |- ( w = <. x , y >. -> <. w , z >. = <. <. x , y >. , z >. )
18	17	eqeq2d 2454	. . . . . . . 8 |- ( w = <. x , y >. -> ( A = <. w , z >. <-> A = <. <. x , y >. , z >. ) )
19	16, 18	ceqsexv 3028	. . . . . . 7 |- ( E. w ( w = <. x , y >. /\ A = <. w , z >. ) <-> A = <. <. x , y >. , z >. )
20	19	exbii 1634	. . . . . 6 |- ( E. z E. w ( w = <. x , y >. /\ A = <. w , z >. ) <-> E. z A = <. <. x , y >. , z >. )
21	15, 20	bitri 249	. . . . 5 |- ( E. w E. z ( w = <. x , y >. /\ A = <. w , z >. ) <-> E. z A = <. <. x , y >. , z >. )
22	21	2exbii 1635	. . . 4 |- ( E. x E. y E. w E. z ( w = <. x , y >. /\ A = <. w , z >. ) <-> E. x E. y E. z A = <. <. x , y >. , z >. )
23	14, 22	bitr3i 251	. . 3 |- ( E. w E. z E. x E. y ( w = <. x , y >. /\ A = <. w , z >. ) <-> E. x E. y E. z A = <. <. x , y >. , z >. )
24	13, 23	bitri 249	. 2 |- ( E. w E. z ( A = <. w , z >. /\ ( w e. ( _V X. _V ) /\ z e. _V ) ) <-> E. x E. y E. z A = <. <. x , y >. , z >. )
25	1, 24	bitri 249	1 |- ( A e. ( ( _V X. _V ) X. _V ) <-> E. x E. y E. z A = <. <. x , y >. , z >. )

Syntax hints:   <-> wb 184   /\ wa 369   = wceq 1369   E.wex 1586   e. wcel 1756   _Vcvv 2991   <.cop 3902   X. cxp 4857

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1591  ax-4 1602  ax-5 1670  ax-6 1708  ax-7 1728  ax-9 1760  ax-10 1775  ax-11 1780  ax-12 1792  ax-13 1943  ax-ext 2423  ax-sep 4432  ax-nul 4440  ax-pr 4550

This theorem depends on definitions:  df-bi 185  df-or 370  df-an 371  df-3an 967  df-tru 1372  df-ex 1587  df-nf 1590  df-sb 1701  df-clab 2430  df-cleq 2436  df-clel 2439  df-nfc 2577  df-ne 2622  df-rab 2743  df-v 2993  df-dif 3350  df-un 3352  df-in 3354  df-ss 3361  df-nul 3657  df-if 3811  df-sn 3897  df-pr 3899  df-op 3903  df-opab 4370  df-xp 4865

This theorem is referenced by:  ssrelrel  4959  dftpos3  6782