Theorem invrfval 19415

Description: Multiplicative inverse function for a division ring. (Contributed by NM, 21-Sep-2011.) (Revised by Mario Carneiro, 25-Dec-2014.)

Hypotheses

Ref	Expression
invrfval.u	⊢ 𝑈 = (Unit‘𝑅)
invrfval.g	⊢ 𝐺 = ((mulGrp‘𝑅) ↾s 𝑈)
invrfval.i	⊢ 𝐼 = (invr‘𝑅)

Assertion

Ref	Expression
invrfval	⊢ 𝐼 = (invg‘𝐺)

Proof of Theorem invrfval

Dummy variable 𝑟 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		invrfval.i	. 2 ⊢ 𝐼 = (invr‘𝑅)
2		fveq2 6663	. . . . . . 7 ⊢ (𝑟 = 𝑅 → (mulGrp‘𝑟) = (mulGrp‘𝑅))
3		fveq2 6663	. . . . . . . 8 ⊢ (𝑟 = 𝑅 → (Unit‘𝑟) = (Unit‘𝑅))
4		invrfval.u	. . . . . . . 8 ⊢ 𝑈 = (Unit‘𝑅)
5	3, 4	syl6eqr 2872	. . . . . . 7 ⊢ (𝑟 = 𝑅 → (Unit‘𝑟) = 𝑈)
6	2, 5	oveq12d 7166	. . . . . 6 ⊢ (𝑟 = 𝑅 → ((mulGrp‘𝑟) ↾s (Unit‘𝑟)) = ((mulGrp‘𝑅) ↾s 𝑈))
7		invrfval.g	. . . . . 6 ⊢ 𝐺 = ((mulGrp‘𝑅) ↾s 𝑈)
8	6, 7	syl6eqr 2872	. . . . 5 ⊢ (𝑟 = 𝑅 → ((mulGrp‘𝑟) ↾s (Unit‘𝑟)) = 𝐺)
9	8	fveq2d 6667	. . . 4 ⊢ (𝑟 = 𝑅 → (invg‘((mulGrp‘𝑟) ↾s (Unit‘𝑟))) = (invg‘𝐺))
10		df-invr 19414	. . . 4 ⊢ invr = (𝑟 ∈ V ↦ (invg‘((mulGrp‘𝑟) ↾s (Unit‘𝑟))))
11		fvex 6676	. . . 4 ⊢ (invg‘𝐺) ∈ V
12	9, 10, 11	fvmpt 6761	. . 3 ⊢ (𝑅 ∈ V → (invr‘𝑅) = (invg‘𝐺))
13		fvprc 6656	. . . . 5 ⊢ (¬ 𝑅 ∈ V → (invr‘𝑅) = ∅)
14		base0 16528	. . . . . . 7 ⊢ ∅ = (Base‘∅)
15		eqid 2819	. . . . . . 7 ⊢ (invg‘∅) = (invg‘∅)
16	14, 15	grpinvfn 18137	. . . . . 6 ⊢ (invg‘∅) Fn ∅
17		fn0 6472	. . . . . 6 ⊢ ((invg‘∅) Fn ∅ ↔ (invg‘∅) = ∅)
18	16, 17	mpbi 232	. . . . 5 ⊢ (invg‘∅) = ∅
19	13, 18	syl6eqr 2872	. . . 4 ⊢ (¬ 𝑅 ∈ V → (invr‘𝑅) = (invg‘∅))
20		fvprc 6656	. . . . . . . 8 ⊢ (¬ 𝑅 ∈ V → (mulGrp‘𝑅) = ∅)
21	20	oveq1d 7163	. . . . . . 7 ⊢ (¬ 𝑅 ∈ V → ((mulGrp‘𝑅) ↾s 𝑈) = (∅ ↾s 𝑈))
22	7, 21	syl5eq 2866	. . . . . 6 ⊢ (¬ 𝑅 ∈ V → 𝐺 = (∅ ↾s 𝑈))
23		ress0 16550	. . . . . 6 ⊢ (∅ ↾s 𝑈) = ∅
24	22, 23	syl6eq 2870	. . . . 5 ⊢ (¬ 𝑅 ∈ V → 𝐺 = ∅)
25	24	fveq2d 6667	. . . 4 ⊢ (¬ 𝑅 ∈ V → (invg‘𝐺) = (invg‘∅))
26	19, 25	eqtr4d 2857	. . 3 ⊢ (¬ 𝑅 ∈ V → (invr‘𝑅) = (invg‘𝐺))
27	12, 26	pm2.61i 184	. 2 ⊢ (invr‘𝑅) = (invg‘𝐺)
28	1, 27	eqtri 2842	1 ⊢ 𝐼 = (invg‘𝐺)

Syntax hints:  ¬ wn 3   = wceq 1530   ∈ wcel 2107  Vcvv 3493  ∅c0 4289   Fn wfn 6343  ‘cfv 6348  (class class class)co 7148   ↾_s cress 16476  inv_gcminusg 18096  mulGrpcmgp 19231  Unitcui 19381  inv_rcinvr 19413

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1789  ax-4 1803  ax-5 1904  ax-6 1963  ax-7 2008  ax-8 2109  ax-9 2117  ax-10 2138  ax-11 2153  ax-12 2169  ax-ext 2791  ax-sep 5194  ax-nul 5201  ax-pow 5257  ax-pr 5320  ax-un 7453

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3an 1083  df-tru 1533  df-ex 1774  df-nf 1778  df-sb 2063  df-mo 2616  df-eu 2648  df-clab 2798  df-cleq 2812  df-clel 2891  df-nfc 2961  df-ne 3015  df-ral 3141  df-rex 3142  df-reu 3143  df-rab 3145  df-v 3495  df-sbc 3771  df-dif 3937  df-un 3939  df-in 3941  df-ss 3950  df-nul 4290  df-if 4466  df-pw 4539  df-sn 4560  df-pr 4562  df-op 4566  df-uni 4831  df-br 5058  df-opab 5120  df-mpt 5138  df-id 5453  df-xp 5554  df-rel 5555  df-cnv 5556  df-co 5557  df-dm 5558  df-rn 5559  df-res 5560  df-ima 5561  df-iota 6307  df-fun 6350  df-fn 6351  df-f 6352  df-fv 6356  df-riota 7106  df-ov 7151  df-oprab 7152  df-mpo 7153  df-slot 16479  df-base 16481  df-ress 16483  df-minusg 18099  df-invr 19414

This theorem is referenced by:  unitinvcl  19416  unitinvinv  19417  unitlinv  19419  unitrinv  19420  invrpropd  19440  subrgugrp  19546  cntzsdrg  19573  cnmsubglem  20600  psgninv  20718  invrvald  21277  invrcn2  22780  nrginvrcn  23293  nrgtdrg  23294  sum2dchr  25842  rdivmuldivd  30855  ringinvval  30856  dvrcan5  30857