Theorem dffv3g 5623

Description: A definition of function value in terms of iota. (Contributed by Jim Kingdon, 29-Dec-2018.)

Assertion

Ref	Expression
dffv3g	|- ( A e. V -> ( F ` A ) = ( iota x x e. ( F " { A } ) ) )

Distinct variable groups:   x, F   x, A   x, V

Proof of Theorem dffv3g

Step	Hyp	Ref	Expression
1		df-fv 5326	. 2 |- ( F ` A ) = ( iota x A F x )
2		vex 2802	. . . 4 |- x e. _V
3		elimasng 5096	. . . . 5 |- ( ( A e. V /\ x e. _V ) -> ( x e. ( F " { A } ) <-> <. A , x >. e. F ) )
4		df-br 4084	. . . . 5 |- ( A F x <-> <. A , x >. e. F )
5	3, 4	bitr4di 198	. . . 4 |- ( ( A e. V /\ x e. _V ) -> ( x e. ( F " { A } ) <-> A F x ) )
6	2, 5	mpan2 425	. . 3 |- ( A e. V -> ( x e. ( F " { A } ) <-> A F x ) )
7	6	iotabidv 5301	. 2 |- ( A e. V -> ( iota x x e. ( F " { A } ) ) = ( iota x A F x ) )
8	1, 7	eqtr4id 2281	1 |- ( A e. V -> ( F ` A ) = ( iota x x e. ( F " { A } ) ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1395   e. wcel 2200   _Vcvv 2799   {csn 3666   <.cop 3669   class class class wbr 4083   "cima 4722   iotacio 5276   ` cfv 5318

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 4202  ax-pow 4258  ax-pr 4293

This theorem depends on definitions:  df-bi 117  df-3an 1004  df-tru 1398  df-nf 1507  df-sb 1809  df-eu 2080  df-mo 2081  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-un 3201  df-in 3203  df-ss 3210  df-pw 3651  df-sn 3672  df-pr 3673  df-op 3675  df-uni 3889  df-br 4084  df-opab 4146  df-xp 4725  df-cnv 4727  df-dm 4729  df-rn 4730  df-res 4731  df-ima 4732  df-iota 5278  df-fv 5326

This theorem is referenced by:  dffv4g  5624  fvco2  5703  shftval  11336