Theorem fvsnun1 6448

Description: The value of a function with one of its ordered pairs replaced, at the replaced ordered pair. See also fvsnun2 6449. (Contributed by NM, 23-Sep-2007.)

Hypotheses

Ref	Expression
fvsnun.1	|- A e. _V
fvsnun.2	|- B e. _V
fvsnun.3	|- G = ( { <. A , B >. } u. ( F |` ( C \ { A } ) ) )

Assertion

Ref	Expression
fvsnun1	|- ( G ` A ) = B

Proof of Theorem fvsnun1

Step	Hyp	Ref	Expression
1		fvsnun.3	. . . . 5 |- G = ( { <. A , B >. } u. ( F |` ( C \ { A } ) ) )
2	1	reseq1i 5392	. . . 4 |- ( G |` { A } ) = ( ( { <. A , B >. } u. ( F |` ( C \ { A } ) ) ) |` { A } )
3		resundir 5411	. . . . 5 |- ( ( { <. A , B >. } u. ( F |` ( C \ { A } ) ) ) |` { A } ) = ( ( { <. A , B >. } |` { A } ) u. ( ( F |` ( C \ { A } ) ) |` { A } ) )
4		incom 3805	. . . . . . . . 9 |- ( ( C \ { A } ) i^i { A } ) = ( { A } i^i ( C \ { A } ) )
5		disjdif 4040	. . . . . . . . 9 |- ( { A } i^i ( C \ { A } ) ) = (/)
6	4, 5	eqtri 2644	. . . . . . . 8 |- ( ( C \ { A } ) i^i { A } ) = (/)
7		resdisj 5563	. . . . . . . 8 |- ( ( ( C \ { A } ) i^i { A } ) = (/) -> ( ( F |` ( C \ { A } ) ) |` { A } ) = (/) )
8	6, 7	ax-mp 5	. . . . . . 7 |- ( ( F |` ( C \ { A } ) ) |` { A } ) = (/)
9	8	uneq2i 3764	. . . . . 6 |- ( ( { <. A , B >. } |` { A } ) u. ( ( F |` ( C \ { A } ) ) |` { A } ) ) = ( ( { <. A , B >. } |` { A } ) u. (/) )
10		un0 3967	. . . . . 6 |- ( ( { <. A , B >. } |` { A } ) u. (/) ) = ( { <. A , B >. } |` { A } )
11	9, 10	eqtri 2644	. . . . 5 |- ( ( { <. A , B >. } |` { A } ) u. ( ( F |` ( C \ { A } ) ) |` { A } ) ) = ( { <. A , B >. } |` { A } )
12	3, 11	eqtri 2644	. . . 4 |- ( ( { <. A , B >. } u. ( F |` ( C \ { A } ) ) ) |` { A } ) = ( { <. A , B >. } |` { A } )
13	2, 12	eqtri 2644	. . 3 |- ( G |` { A } ) = ( { <. A , B >. } |` { A } )
14	13	fveq1i 6192	. 2 |- ( ( G |` { A } ) ` A ) = ( ( { <. A , B >. } |` { A } ) ` A )
15		fvsnun.1	. . . 4 |- A e. _V
16	15	snid 4208	. . 3 |- A e. { A }
17		fvres 6207	. . 3 |- ( A e. { A } -> ( ( G |` { A } ) ` A ) = ( G ` A ) )
18	16, 17	ax-mp 5	. 2 |- ( ( G |` { A } ) ` A ) = ( G ` A )
19		fvres 6207	. . . 4 |- ( A e. { A } -> ( ( { <. A , B >. } |` { A } ) ` A ) = ( { <. A , B >. } ` A ) )
20	16, 19	ax-mp 5	. . 3 |- ( ( { <. A , B >. } |` { A } ) ` A ) = ( { <. A , B >. } ` A )
21		fvsnun.2	. . . 4 |- B e. _V
22	15, 21	fvsn 6446	. . 3 |- ( { <. A , B >. } ` A ) = B
23	20, 22	eqtri 2644	. 2 |- ( ( { <. A , B >. } |` { A } ) ` A ) = B
24	14, 18, 23	3eqtr3i 2652	1 |- ( G ` A ) = B

Syntax hints:   = wceq 1483   e. wcel 1990   _Vcvv 3200   \ cdif 3571   u. cun 3572   i^i cin 3573   (/)c0 3915   {csn 4177   <.cop 4183   |` cres 5116   ` cfv 5888

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-sep 4781  ax-nul 4789  ax-pr 4906

This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ral 2917  df-rex 2918  df-rab 2921  df-v 3202  df-sbc 3436  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-nul 3916  df-if 4087  df-sn 4178  df-pr 4180  df-op 4184  df-uni 4437  df-br 4654  df-opab 4713  df-id 5024  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-res 5126  df-iota 5851  df-fun 5890  df-fv 5896

This theorem is referenced by:  fac0  13063  ruclem4  14963