Theorem opeliunxp 4748

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 2788	. 2 |- ( <. x , C >. e. U_ x e. A ( { x } X. B ) -> <. x , C >. e. _V )
2		opexg 4290	. 2 |- ( ( x e. A /\ C e. B ) -> <. x , C >. e. _V )
3		df-rex 2492	. . . . . 6 |- ( E. x e. A y e. ( { x } X. B ) <-> E. x ( x e. A /\ y e. ( { x } X. B ) ) )
4		nfv 1552	. . . . . . 7 |- F/ z ( x e. A /\ y e. ( { x } X. B ) )
5		nfs1v 1968	. . . . . . . 8 |- F/ x [ z / x ] x e. A
6		nfcv 2350	. . . . . . . . . 10 |- F/_ x { z }
7		nfcsb1v 3134	. . . . . . . . . 10 |- F/_ x [_ z / x ]_ B
8	6, 7	nfxp 4720	. . . . . . . . 9 |- F/_ x ( { z } X. [_ z / x ]_ B )
9	8	nfcri 2344	. . . . . . . 8 |- F/ x y e. ( { z } X. [_ z / x ]_ B )
10	5, 9	nfan 1589	. . . . . . 7 |- F/ x ( [ z / x ] x e. A /\ y e. ( { z } X. [_ z / x ]_ B ) )
11		sbequ12 1795	. . . . . . . 8 |- ( x = z -> ( x e. A <-> [ z / x ] x e. A ) )
12		sneq 3654	. . . . . . . . . 10 |- ( x = z -> { x } = { z } )
13		csbeq1a 3110	. . . . . . . . . 10 |- ( x = z -> B = [_ z / x ]_ B )
14	12, 13	xpeq12d 4718	. . . . . . . . 9 |- ( x = z -> ( { x } X. B ) = ( { z } X. [_ z / x ]_ B ) )
15	14	eleq2d 2277	. . . . . . . 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 1780	. . . . . 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 2270	. . . . . . 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 1849	. . . . 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 3943	. . . 4 |- U_ x e. A ( { x } X. B ) = { y | E. x e. A y e. ( { x } X. B ) }
24	22, 23	elab2g 2927	. . 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 4723	. . . . . . 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 3660	. . . . . . . 8 |- ( x e. { z } <-> x = z )
29		equcom 1730	. . . . . . . 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 1629	. . . 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 2779	. . . . 5 |- x e. _V
35		sbequ12r 1796	. . . . . 6 |- ( z = x -> ( [ z / x ] x e. A <-> x e. A ) )
36	13	equcoms 1732	. . . . . . . 8 |- ( z = x -> B = [_ z / x ]_ B )
37	36	eqcomd 2213	. . . . . . 7 |- ( z = x -> [_ z / x ]_ B = B )
38	37	eleq2d 2277	. . . . . 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 2816	. . . 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 706	1 |- ( <. x , C >. e. U_ x e. A ( { x } X. B ) <-> ( x e. A /\ C e. B ) )

Syntax hints:   /\ wa 104   <-> wb 105   = wceq 1373   E.wex 1516   [wsb 1786   e. wcel 2178   E.wrex 2487   _Vcvv 2776   [_csb 3101   {csn 3643   <.cop 3646   U_ciun 3941   X. cxp 4691

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 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-10 1529  ax-11 1530  ax-i12 1531  ax-bndl 1533  ax-4 1534  ax-17 1550  ax-i9 1554  ax-ial 1558  ax-i5r 1559  ax-14 2181  ax-ext 2189  ax-sep 4178  ax-pow 4234  ax-pr 4269

This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-nf 1485  df-sb 1787  df-clab 2194  df-cleq 2200  df-clel 2203  df-nfc 2339  df-ral 2491  df-rex 2492  df-v 2778  df-sbc 3006  df-csb 3102  df-un 3178  df-in 3180  df-ss 3187  df-pw 3628  df-sn 3649  df-pr 3650  df-op 3652  df-iun 3943  df-opab 4122  df-xp 4699

This theorem is referenced by:  eliunxp  4835  opeliunxp2  4836  opeliunxp2f  6347