Theorem funiunfv 6146

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 5625	. . . 4 |- ( Fun F -> Fun ( F |` A ) )
2		funfn 5615	. . . 4 |- ( Fun ( F |` A ) <-> ( F |` A ) Fn dom ( F |` A ) )
3	1, 2	sylib 196	. . 3 |- ( Fun F -> ( F |` A ) Fn dom ( F |` A ) )
4		fniunfv 6145	. . 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 3903	. . . . 5 |- ( dom ( F |` A ) u. ( A \ dom ( F |` A ) ) ) = ( dom ( F |` A ) u. A )
7		dmres 5292	. . . . . . 7 |- dom ( F |` A ) = ( A i^i dom F )
8		inss1 3718	. . . . . . 7 |- ( A i^i dom F ) C_ A
9	7, 8	eqsstri 3534	. . . . . 6 |- dom ( F |` A ) C_ A
10		ssequn1 3674	. . . . . 6 |- ( dom ( F |` A ) C_ A <-> ( dom ( F |` A ) u. A ) = A )
11	9, 10	mpbi 208	. . . . 5 |- ( dom ( F |` A ) u. A ) = A
12	6, 11	eqtri 2496	. . . 4 |- ( dom ( F |` A ) u. ( A \ dom ( F |` A ) ) ) = A
13		iuneq1 4339	. . . 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 5	. . 3 |- U_ x e. ( dom ( F |` A ) u. ( A \ dom ( F |` A ) ) ) ( ( F |` A ) ` x ) = U_ x e. A ( ( F |` A ) ` x )
15		iunxun 4407	. . . 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 3627	. . . . . . . . 9 |- ( x e. ( A \ dom ( F |` A ) ) -> -. x e. dom ( F |` A ) )
17		ndmfv 5888	. . . . . . . . 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 4344	. . . . . . 7 |- U_ x e. ( A \ dom ( F |` A ) ) ( ( F |` A ) ` x ) = U_ x e. ( A \ dom ( F |` A ) ) (/)
20		iun0 4381	. . . . . . 7 |- U_ x e. ( A \ dom ( F |` A ) ) (/) = (/)
21	19, 20	eqtri 2496	. . . . . 6 |- U_ x e. ( A \ dom ( F |` A ) ) ( ( F |` A ) ` x ) = (/)
22	21	uneq2i 3655	. . . . 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 3810	. . . . 5 |- ( U_ x e. dom ( F |` A ) ( ( F |` A ) ` x ) u. (/) ) = U_ x e. dom ( F |` A ) ( ( F |` A ) ` x )
24	22, 23	eqtri 2496	. . . 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 2496	. . 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 5878	. . . 4 |- ( x e. A -> ( ( F |` A ) ` x ) = ( F ` x ) )
27	26	iuneq2i 4344	. . 3 |- U_ x e. A ( ( F |` A ) ` x ) = U_ x e. A ( F ` x )
28	14, 25, 27	3eqtr3ri 2505	. 2 |- U_ x e. A ( F ` x ) = U_ x e. dom ( F |` A ) ( ( F |` A ) ` x )
29		df-ima 5012	. . 3 |- ( F " A ) = ran ( F |` A )
30	29	unieqi 4254	. 2 |- U. ( F " A ) = U. ran ( F |` A )
31	5, 28, 30	3eqtr4g 2533	1 |- ( Fun F -> U_ x e. A ( F ` x ) = U. ( F " A ) )

Syntax hints:   -. wn 3   -> wi 4   = wceq 1379   e. wcel 1767   \ cdif 3473   u. cun 3474   i^i cin 3475   C_ wss 3476   (/)c0 3785   U.cuni 4245   U_ciun 4325   dom cdm 4999   ran crn 5000   |` cres 5001   "cima 5002   Fun wfun 5580   Fn wfn 5581   ` cfv 5586

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1601  ax-4 1612  ax-5 1680  ax-6 1719  ax-7 1739  ax-8 1769  ax-9 1771  ax-10 1786  ax-11 1791  ax-12 1803  ax-13 1968  ax-ext 2445  ax-sep 4568  ax-nul 4576  ax-pow 4625  ax-pr 4686

This theorem depends on definitions:  df-bi 185  df-or 370  df-an 371  df-3an 975  df-tru 1382  df-ex 1597  df-nf 1600  df-sb 1712  df-eu 2279  df-mo 2280  df-clab 2453  df-cleq 2459  df-clel 2462  df-nfc 2617  df-ne 2664  df-ral 2819  df-rex 2820  df-rab 2823  df-v 3115  df-sbc 3332  df-dif 3479  df-un 3481  df-in 3483  df-ss 3490  df-nul 3786  df-if 3940  df-sn 4028  df-pr 4030  df-op 4034  df-uni 4246  df-iun 4327  df-br 4448  df-opab 4506  df-mpt 4507  df-id 4795  df-xp 5005  df-rel 5006  df-cnv 5007  df-co 5008  df-dm 5009  df-rn 5010  df-res 5011  df-ima 5012  df-iota 5549  df-fun 5588  df-fn 5589  df-fv 5594

This theorem is referenced by:  funiunfvf  6147  eluniima  6148  marypha2lem4  7894  r1limg  8185  r1elssi  8219  r1elss  8220  ackbij2  8619  r1om  8620  ttukeylem6  8890  isacs2  14904  mreacs  14909  acsfn  14910  isacs5  15655  dprdss  16866  dprd2dlem1  16880  dmdprdsplit2lem  16884  uniioombllem3a  21728  uniioombllem4  21730  uniioombllem5  21731  dyadmbl  21744  mblfinlem1  29628  ovoliunnfl  29633  voliunnfl  29635