Theorem subval 8218

Description: Value of subtraction, which is the (unique) element x such that B + x = A. (Contributed by NM, 4-Aug-2007.) (Revised by Mario Carneiro, 2-Nov-2013.)

Assertion

Ref	Expression
subval	|- ( ( A e. CC /\ B e. CC ) -> ( A - B ) = ( iota_ x e. CC ( B + x ) = A ) )

Distinct variable groups:   x, A   x, B

Proof of Theorem subval

Dummy variables y z are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		negeu 8217	. . . 4 |- ( ( B e. CC /\ A e. CC ) -> E! x e. CC ( B + x ) = A )
2		riotacl 5892	. . . 4 |- ( E! x e. CC ( B + x ) = A -> ( iota_ x e. CC ( B + x ) = A ) e. CC )
3	1, 2	syl 14	. . 3 |- ( ( B e. CC /\ A e. CC ) -> ( iota_ x e. CC ( B + x ) = A ) e. CC )
4	3	ancoms 268	. 2 |- ( ( A e. CC /\ B e. CC ) -> ( iota_ x e. CC ( B + x ) = A ) e. CC )
5		eqeq2 2206	. . . 4 |- ( y = A -> ( ( z + x ) = y <-> ( z + x ) = A ) )
6	5	riotabidv 5879	. . 3 |- ( y = A -> ( iota_ x e. CC ( z + x ) = y ) = ( iota_ x e. CC ( z + x ) = A ) )
7		oveq1 5929	. . . . 5 |- ( z = B -> ( z + x ) = ( B + x ) )
8	7	eqeq1d 2205	. . . 4 |- ( z = B -> ( ( z + x ) = A <-> ( B + x ) = A ) )
9	8	riotabidv 5879	. . 3 |- ( z = B -> ( iota_ x e. CC ( z + x ) = A ) = ( iota_ x e. CC ( B + x ) = A ) )
10		df-sub 8199	. . 3 |- - = ( y e. CC , z e. CC |-> ( iota_ x e. CC ( z + x ) = y ) )
11	6, 9, 10	ovmpog 6057	. 2 |- ( ( A e. CC /\ B e. CC /\ ( iota_ x e. CC ( B + x ) = A ) e. CC ) -> ( A - B ) = ( iota_ x e. CC ( B + x ) = A ) )
12	4, 11	mpd3an3 1349	1 |- ( ( A e. CC /\ B e. CC ) -> ( A - B ) = ( iota_ x e. CC ( B + x ) = A ) )

Syntax hints:   -> wi 4   /\ wa 104   = wceq 1364   e. wcel 2167   E!wreu 2477   iota_crio 5876  (class class class)co 5922   CCcc 7877   + caddc 7882   - cmin 8197

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-in1 615  ax-in2 616  ax-io 710  ax-5 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-10 1519  ax-11 1520  ax-i12 1521  ax-bndl 1523  ax-4 1524  ax-17 1540  ax-i9 1544  ax-ial 1548  ax-i5r 1549  ax-14 2170  ax-ext 2178  ax-sep 4151  ax-pow 4207  ax-pr 4242  ax-setind 4573  ax-resscn 7971  ax-1cn 7972  ax-icn 7974  ax-addcl 7975  ax-addrcl 7976  ax-mulcl 7977  ax-addcom 7979  ax-addass 7981  ax-distr 7983  ax-i2m1 7984  ax-0id 7987  ax-rnegex 7988  ax-cnre 7990

This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1367  df-fal 1370  df-nf 1475  df-sb 1777  df-eu 2048  df-mo 2049  df-clab 2183  df-cleq 2189  df-clel 2192  df-nfc 2328  df-ne 2368  df-ral 2480  df-rex 2481  df-reu 2482  df-rab 2484  df-v 2765  df-sbc 2990  df-dif 3159  df-un 3161  df-in 3163  df-ss 3170  df-pw 3607  df-sn 3628  df-pr 3629  df-op 3631  df-uni 3840  df-br 4034  df-opab 4095  df-id 4328  df-xp 4669  df-rel 4670  df-cnv 4671  df-co 4672  df-dm 4673  df-iota 5219  df-fun 5260  df-fv 5266  df-riota 5877  df-ov 5925  df-oprab 5926  df-mpo 5927  df-sub 8199

This theorem is referenced by:  subcl  8225  subf  8228  subadd  8229