Theorem opeliunxp 4773

Description: Membership in a union of cross products. (Contributed by Mario Carneiro, 29-Dec-2014.) (Revised by Mario Carneiro, 1-Jan-2017.)

Assertion

Ref	Expression
opeliunxp	|- ( <. x , C >. e. U_ x e. A ( { x } X. B ) <-> ( x e. A /\ C e. B ) )

Proof of Theorem opeliunxp

Dummy variables y z are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		elex 2811	. 2 |- ( <. x , C >. e. U_ x e. A ( { x } X. B ) -> <. x , C >. e. _V )
2		opexg 4313	. 2 |- ( ( x e. A /\ C e. B ) -> <. x , C >. e. _V )
3		df-rex 2514	. . . . . 6 |- ( E. x e. A y e. ( { x } X. B ) <-> E. x ( x e. A /\ y e. ( { x } X. B ) ) )
4		nfv 1574	. . . . . . 7 |- F/ z ( x e. A /\ y e. ( { x } X. B ) )
5		nfs1v 1990	. . . . . . . 8 |- F/ x [ z / x ] x e. A
6		nfcv 2372	. . . . . . . . . 10 |- F/_ x { z }
7		nfcsb1v 3157	. . . . . . . . . 10 |- F/_ x [_ z / x ]_ B
8	6, 7	nfxp 4745	. . . . . . . . 9 |- F/_ x ( { z } X. [_ z / x ]_ B )
9	8	nfcri 2366	. . . . . . . 8 |- F/ x y e. ( { z } X. [_ z / x ]_ B )
10	5, 9	nfan 1611	. . . . . . 7 |- F/ x ( [ z / x ] x e. A /\ y e. ( { z } X. [_ z / x ]_ B ) )
11		sbequ12 1817	. . . . . . . 8 |- ( x = z -> ( x e. A <-> [ z / x ] x e. A ) )
12		sneq 3677	. . . . . . . . . 10 |- ( x = z -> { x } = { z } )
13		csbeq1a 3133	. . . . . . . . . 10 |- ( x = z -> B = [_ z / x ]_ B )
14	12, 13	xpeq12d 4743	. . . . . . . . 9 |- ( x = z -> ( { x } X. B ) = ( { z } X. [_ z / x ]_ B ) )
15	14	eleq2d 2299	. . . . . . . 8 |- ( x = z -> ( y e. ( { x } X. B ) <-> y e. ( { z } X. [_ z / x ]_ B ) ) )
16	11, 15	anbi12d 473	. . . . . . 7 |- ( x = z -> ( ( x e. A /\ y e. ( { x } X. B ) ) <-> ( [ z / x ] x e. A /\ y e. ( { z } X. [_ z / x ]_ B ) ) ) )
17	4, 10, 16	cbvex 1802	. . . . . 6 |- ( E. x ( x e. A /\ y e. ( { x } X. B ) ) <-> E. z ( [ z / x ] x e. A /\ y e. ( { z } X. [_ z / x ]_ B ) ) )
18	3, 17	bitri 184	. . . . 5 |- ( E. x e. A y e. ( { x } X. B ) <-> E. z ( [ z / x ] x e. A /\ y e. ( { z } X. [_ z / x ]_ B ) ) )
19		eleq1 2292	. . . . . . 7 |- ( y = <. x , C >. -> ( y e. ( { z } X. [_ z / x ]_ B ) <-> <. x , C >. e. ( { z } X. [_ z / x ]_ B ) ) )
20	19	anbi2d 464	. . . . . 6 |- ( y = <. x , C >. -> ( ( [ z / x ] x e. A /\ y e. ( { z } X. [_ z / x ]_ B ) ) <-> ( [ z / x ] x e. A /\ <. x , C >. e. ( { z } X. [_ z / x ]_ B ) ) ) )
21	20	exbidv 1871	. . . . 5 |- ( y = <. x , C >. -> ( E. z ( [ z / x ] x e. A /\ y e. ( { z } X. [_ z / x ]_ B ) ) <-> E. z ( [ z / x ] x e. A /\ <. x , C >. e. ( { z } X. [_ z / x ]_ B ) ) ) )
22	18, 21	bitrid 192	. . . 4 |- ( y = <. x , C >. -> ( E. x e. A y e. ( { x } X. B ) <-> E. z ( [ z / x ] x e. A /\ <. x , C >. e. ( { z } X. [_ z / x ]_ B ) ) ) )
23		df-iun 3966	. . . 4 |- U_ x e. A ( { x } X. B ) = { y | E. x e. A y e. ( { x } X. B ) }
24	22, 23	elab2g 2950	. . 3 |- ( <. x , C >. e. _V -> ( <. x , C >. e. U_ x e. A ( { x } X. B ) <-> E. z ( [ z / x ] x e. A /\ <. x , C >. e. ( { z } X. [_ z / x ]_ B ) ) ) )
25		opelxp 4748	. . . . . . 7 |- ( <. x , C >. e. ( { z } X. [_ z / x ]_ B ) <-> ( x e. { z } /\ C e. [_ z / x ]_ B ) )
26	25	anbi2i 457	. . . . . 6 |- ( ( [ z / x ] x e. A /\ <. x , C >. e. ( { z } X. [_ z / x ]_ B ) ) <-> ( [ z / x ] x e. A /\ ( x e. { z } /\ C e. [_ z / x ]_ B ) ) )
27		an12 561	. . . . . 6 |- ( ( [ z / x ] x e. A /\ ( x e. { z } /\ C e. [_ z / x ]_ B ) ) <-> ( x e. { z } /\ ( [ z / x ] x e. A /\ C e. [_ z / x ]_ B ) ) )
28		velsn 3683	. . . . . . . 8 |- ( x e. { z } <-> x = z )
29		equcom 1752	. . . . . . . 8 |- ( x = z <-> z = x )
30	28, 29	bitri 184	. . . . . . 7 |- ( x e. { z } <-> z = x )
31	30	anbi1i 458	. . . . . 6 |- ( ( x e. { z } /\ ( [ z / x ] x e. A /\ C e. [_ z / x ]_ B ) ) <-> ( z = x /\ ( [ z / x ] x e. A /\ C e. [_ z / x ]_ B ) ) )
32	26, 27, 31	3bitri 206	. . . . 5 |- ( ( [ z / x ] x e. A /\ <. x , C >. e. ( { z } X. [_ z / x ]_ B ) ) <-> ( z = x /\ ( [ z / x ] x e. A /\ C e. [_ z / x ]_ B ) ) )
33	32	exbii 1651	. . . 4 |- ( E. z ( [ z / x ] x e. A /\ <. x , C >. e. ( { z } X. [_ z / x ]_ B ) ) <-> E. z ( z = x /\ ( [ z / x ] x e. A /\ C e. [_ z / x ]_ B ) ) )
34		vex 2802	. . . . 5 |- x e. _V
35		sbequ12r 1818	. . . . . 6 |- ( z = x -> ( [ z / x ] x e. A <-> x e. A ) )
36	13	equcoms 1754	. . . . . . . 8 |- ( z = x -> B = [_ z / x ]_ B )
37	36	eqcomd 2235	. . . . . . 7 |- ( z = x -> [_ z / x ]_ B = B )
38	37	eleq2d 2299	. . . . . 6 |- ( z = x -> ( C e. [_ z / x ]_ B <-> C e. B ) )
39	35, 38	anbi12d 473	. . . . 5 |- ( z = x -> ( ( [ z / x ] x e. A /\ C e. [_ z / x ]_ B ) <-> ( x e. A /\ C e. B ) ) )
40	34, 39	ceqsexv 2839	. . . 4 |- ( E. z ( z = x /\ ( [ z / x ] x e. A /\ C e. [_ z / x ]_ B ) ) <-> ( x e. A /\ C e. B ) )
41	33, 40	bitri 184	. . 3 |- ( E. z ( [ z / x ] x e. A /\ <. x , C >. e. ( { z } X. [_ z / x ]_ B ) ) <-> ( x e. A /\ C e. B ) )
42	24, 41	bitrdi 196	. 2 |- ( <. x , C >. e. _V -> ( <. x , C >. e. U_ x e. A ( { x } X. B ) <-> ( x e. A /\ C e. B ) ) )
43	1, 2, 42	pm5.21nii 709	1 |- ( <. x , C >. e. U_ x e. A ( { x } X. B ) <-> ( x e. A /\ C e. B ) )

Syntax hints:   /\ wa 104   <-> wb 105   = wceq 1395   E.wex 1538   [wsb 1808   e. wcel 2200   E.wrex 2509   _Vcvv 2799   [_csb 3124   {csn 3666   <.cop 3669   U_ciun 3964   X. cxp 4716

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 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-14 2203  ax-ext 2211  ax-sep 4201  ax-pow 4257  ax-pr 4292

This theorem depends on definitions:  df-bi 117  df-3an 1004  df-tru 1398  df-nf 1507  df-sb 1809  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ral 2513  df-rex 2514  df-v 2801  df-sbc 3029  df-csb 3125  df-un 3201  df-in 3203  df-ss 3210  df-pw 3651  df-sn 3672  df-pr 3673  df-op 3675  df-iun 3966  df-opab 4145  df-xp 4724

This theorem is referenced by:  eliunxp  4860  opeliunxp2  4861  opeliunxp2f  6382