Theorem funiunfv 5954

Description: The indexed union of a function's values is the union of its image under the index class.

Note: This theorem depends on the fact that our function value is the empty set outside of its domain. If the antecedent is changed to F Fn A, the theorem can be proved without this dependency. (Contributed by NM, 26-Mar-2006.) (Proof shortened by Mario Carneiro, 31-Aug-2015.)

Assertion

Ref	Expression
funiunfv	|- ( Fun F -> U_ x e. A ( F ` x ) = U. ( F " A ) )

Distinct variable groups:   x, A   x, F

Proof of Theorem funiunfv

Step	Hyp	Ref	Expression
1		funres 5451	. . . 4 |- ( Fun F -> Fun ( F |` A ) )
2		funfn 5441	. . . 4 |- ( Fun ( F |` A ) <-> ( F |` A ) Fn dom ( F |` A ) )
3	1, 2	sylib 189	. . 3 |- ( Fun F -> ( F |` A ) Fn dom ( F |` A ) )
4		fniunfv 5953	. . 3 |- ( ( F |` A ) Fn dom ( F |` A ) -> U_ x e. dom ( F |` A ) ( ( F |` A ) ` x ) = U. ran ( F |` A ) )
5	3, 4	syl 16	. 2 |- ( Fun F -> U_ x e. dom ( F |` A ) ( ( F |` A ) ` x ) = U. ran ( F |` A ) )
6		undif2 3664	. . . . 5 |- ( dom ( F |` A ) u. ( A \ dom ( F |` A ) ) ) = ( dom ( F |` A ) u. A )
7		dmres 5126	. . . . . . 7 |- dom ( F |` A ) = ( A i^i dom F )
8		inss1 3521	. . . . . . 7 |- ( A i^i dom F ) C_ A
9	7, 8	eqsstri 3338	. . . . . 6 |- dom ( F |` A ) C_ A
10		ssequn1 3477	. . . . . 6 |- ( dom ( F |` A ) C_ A <-> ( dom ( F |` A ) u. A ) = A )
11	9, 10	mpbi 200	. . . . 5 |- ( dom ( F |` A ) u. A ) = A
12	6, 11	eqtri 2424	. . . 4 |- ( dom ( F |` A ) u. ( A \ dom ( F |` A ) ) ) = A
13		iuneq1 4066	. . . 4 |- ( ( dom ( F |` A ) u. ( A \ dom ( F |` A ) ) ) = A -> U_ x e. ( dom ( F |` A ) u. ( A \ dom ( F |` A ) ) ) ( ( F |` A ) ` x ) = U_ x e. A ( ( F |` A ) ` x ) )
14	12, 13	ax-mp 8	. . 3 |- U_ x e. ( dom ( F |` A ) u. ( A \ dom ( F |` A ) ) ) ( ( F |` A ) ` x ) = U_ x e. A ( ( F |` A ) ` x )
15		iunxun 4132	. . . 4 |- U_ x e. ( dom ( F |` A ) u. ( A \ dom ( F |` A ) ) ) ( ( F |` A ) ` x ) = ( U_ x e. dom ( F |` A ) ( ( F |` A ) ` x ) u. U_ x e. ( A \ dom ( F |` A ) ) ( ( F |` A ) ` x ) )
16		eldifn 3430	. . . . . . . . 9 |- ( x e. ( A \ dom ( F |` A ) ) -> -. x e. dom ( F |` A ) )
17		ndmfv 5714	. . . . . . . . 9 |- ( -. x e. dom ( F |` A ) -> ( ( F |` A ) ` x ) = (/) )
18	16, 17	syl 16	. . . . . . . 8 |- ( x e. ( A \ dom ( F |` A ) ) -> ( ( F |` A ) ` x ) = (/) )
19	18	iuneq2i 4071	. . . . . . 7 |- U_ x e. ( A \ dom ( F |` A ) ) ( ( F |` A ) ` x ) = U_ x e. ( A \ dom ( F |` A ) ) (/)
20		iun0 4107	. . . . . . 7 |- U_ x e. ( A \ dom ( F |` A ) ) (/) = (/)
21	19, 20	eqtri 2424	. . . . . 6 |- U_ x e. ( A \ dom ( F |` A ) ) ( ( F |` A ) ` x ) = (/)
22	21	uneq2i 3458	. . . . 5 |- ( U_ x e. dom ( F |` A ) ( ( F |` A ) ` x ) u. U_ x e. ( A \ dom ( F |` A ) ) ( ( F |` A ) ` x ) ) = ( U_ x e. dom ( F |` A ) ( ( F |` A ) ` x ) u. (/) )
23		un0 3612	. . . . 5 |- ( U_ x e. dom ( F |` A ) ( ( F |` A ) ` x ) u. (/) ) = U_ x e. dom ( F |` A ) ( ( F |` A ) ` x )
24	22, 23	eqtri 2424	. . . 4 |- ( U_ x e. dom ( F |` A ) ( ( F |` A ) ` x ) u. U_ x e. ( A \ dom ( F |` A ) ) ( ( F |` A ) ` x ) ) = U_ x e. dom ( F |` A ) ( ( F |` A ) ` x )
25	15, 24	eqtri 2424	. . 3 |- U_ x e. ( dom ( F |` A ) u. ( A \ dom ( F |` A ) ) ) ( ( F |` A ) ` x ) = U_ x e. dom ( F |` A ) ( ( F |` A ) ` x )
26		fvres 5704	. . . 4 |- ( x e. A -> ( ( F |` A ) ` x ) = ( F ` x ) )
27	26	iuneq2i 4071	. . 3 |- U_ x e. A ( ( F |` A ) ` x ) = U_ x e. A ( F ` x )
28	14, 25, 27	3eqtr3ri 2433	. 2 |- U_ x e. A ( F ` x ) = U_ x e. dom ( F |` A ) ( ( F |` A ) ` x )
29		df-ima 4850	. . 3 |- ( F " A ) = ran ( F |` A )
30	29	unieqi 3985	. 2 |- U. ( F " A ) = U. ran ( F |` A )
31	5, 28, 30	3eqtr4g 2461	1 |- ( Fun F -> U_ x e. A ( F ` x ) = U. ( F " A ) )

Syntax hints:   -. wn 3   -> wi 4   = wceq 1649   e. wcel 1721   \ cdif 3277   u. cun 3278   i^i cin 3279   C_ wss 3280   (/)c0 3588   U.cuni 3975   U_ciun 4053   dom cdm 4837   ran crn 4838   |` cres 4839   "cima 4840   Fun wfun 5407   Fn wfn 5408   ` cfv 5413

This theorem is referenced by:  funiunfvf  5955  eluniima  5956  marypha2lem4  7401  r1limg  7653  r1elssi  7687  r1elss  7688  ackbij2  8079  r1om  8080  ttukeylem6  8350  isacs2  13833  mreacs  13838  acsfn  13839  isacs5  14553  dprdss  15542  dprd2dlem1  15554  dmdprdsplit2lem  15558  uniioombllem3a  19429  uniioombllem4  19431  uniioombllem5  19432  dyadmbl  19445  mblfinlem  26143  ovoliunnfl  26147  voliunnfl  26149

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-3 7  ax-mp 8  ax-gen 1552  ax-5 1563  ax-17 1623  ax-9 1662  ax-8 1683  ax-13 1723  ax-14 1725  ax-6 1740  ax-7 1745  ax-11 1757  ax-12 1946  ax-ext 2385  ax-sep 4290  ax-nul 4298  ax-pow 4337  ax-pr 4363

This theorem depends on definitions:  df-bi 178  df-or 360  df-an 361  df-3an 938  df-tru 1325  df-ex 1548  df-nf 1551  df-sb 1656  df-eu 2258  df-mo 2259  df-clab 2391  df-cleq 2397  df-clel 2400  df-nfc 2529  df-ne 2569  df-ral 2671  df-rex 2672  df-rab 2675  df-v 2918  df-sbc 3122  df-dif 3283  df-un 3285  df-in 3287  df-ss 3294  df-nul 3589  df-if 3700  df-sn 3780  df-pr 3781  df-op 3783  df-uni 3976  df-iun 4055  df-br 4173  df-opab 4227  df-mpt 4228  df-id 4458  df-xp 4843  df-rel 4844  df-cnv 4845  df-co 4846  df-dm 4847  df-rn 4848  df-res 4849  df-ima 4850  df-iota 5377  df-fun 5415  df-fn 5416  df-fv 5421