Theorem invrfval 18496

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 6103	. . . . . . 7 ⊢ (𝑟 = 𝑅 → (mulGrp‘𝑟) = (mulGrp‘𝑅))
3		fveq2 6103	. . . . . . . 8 ⊢ (𝑟 = 𝑅 → (Unit‘𝑟) = (Unit‘𝑅))
4		invrfval.u	. . . . . . . 8 ⊢ 𝑈 = (Unit‘𝑅)
5	3, 4	syl6eqr 2662	. . . . . . 7 ⊢ (𝑟 = 𝑅 → (Unit‘𝑟) = 𝑈)
6	2, 5	oveq12d 6567	. . . . . 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 2662	. . . . 5 ⊢ (𝑟 = 𝑅 → ((mulGrp‘𝑟) ↾s (Unit‘𝑟)) = 𝐺)
9	8	fveq2d 6107	. . . 4 ⊢ (𝑟 = 𝑅 → (invg‘((mulGrp‘𝑟) ↾s (Unit‘𝑟))) = (invg‘𝐺))
10		df-invr 18495	. . . 4 ⊢ invr = (𝑟 ∈ V ↦ (invg‘((mulGrp‘𝑟) ↾s (Unit‘𝑟))))
11		fvex 6113	. . . 4 ⊢ (invg‘𝐺) ∈ V
12	9, 10, 11	fvmpt 6191	. . 3 ⊢ (𝑅 ∈ V → (invr‘𝑅) = (invg‘𝐺))
13		fvprc 6097	. . . . 5 ⊢ (¬ 𝑅 ∈ V → (invr‘𝑅) = ∅)
14		base0 15740	. . . . . . 7 ⊢ ∅ = (Base‘∅)
15		eqid 2610	. . . . . . 7 ⊢ (invg‘∅) = (invg‘∅)
16	14, 15	grpinvfn 17285	. . . . . 6 ⊢ (invg‘∅) Fn ∅
17		fn0 5924	. . . . . 6 ⊢ ((invg‘∅) Fn ∅ ↔ (invg‘∅) = ∅)
18	16, 17	mpbi 219	. . . . 5 ⊢ (invg‘∅) = ∅
19	13, 18	syl6eqr 2662	. . . 4 ⊢ (¬ 𝑅 ∈ V → (invr‘𝑅) = (invg‘∅))
20		fvprc 6097	. . . . . . . 8 ⊢ (¬ 𝑅 ∈ V → (mulGrp‘𝑅) = ∅)
21	20	oveq1d 6564	. . . . . . 7 ⊢ (¬ 𝑅 ∈ V → ((mulGrp‘𝑅) ↾s 𝑈) = (∅ ↾s 𝑈))
22	7, 21	syl5eq 2656	. . . . . 6 ⊢ (¬ 𝑅 ∈ V → 𝐺 = (∅ ↾s 𝑈))
23		ress0 15761	. . . . . 6 ⊢ (∅ ↾s 𝑈) = ∅
24	22, 23	syl6eq 2660	. . . . 5 ⊢ (¬ 𝑅 ∈ V → 𝐺 = ∅)
25	24	fveq2d 6107	. . . 4 ⊢ (¬ 𝑅 ∈ V → (invg‘𝐺) = (invg‘∅))
26	19, 25	eqtr4d 2647	. . 3 ⊢ (¬ 𝑅 ∈ V → (invr‘𝑅) = (invg‘𝐺))
27	12, 26	pm2.61i 175	. 2 ⊢ (invr‘𝑅) = (invg‘𝐺)
28	1, 27	eqtri 2632	1 ⊢ 𝐼 = (invg‘𝐺)

Syntax hints:  ¬ wn 3   = wceq 1475   ∈ wcel 1977  Vcvv 3173  ∅c0 3874   Fn wfn 5799  ‘cfv 5804  (class class class)co 6549   ↾_s cress 15696  inv_gcminusg 17246  mulGrpcmgp 18312  Unitcui 18462  inv_rcinvr 18494

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875  ax-7 1922  ax-8 1979  ax-9 1986  ax-10 2006  ax-11 2021  ax-12 2034  ax-13 2234  ax-ext 2590  ax-rep 4699  ax-sep 4709  ax-nul 4717  ax-pow 4769  ax-pr 4833

This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-3an 1033  df-tru 1478  df-ex 1696  df-nf 1701  df-sb 1868  df-eu 2462  df-mo 2463  df-clab 2597  df-cleq 2603  df-clel 2606  df-nfc 2740  df-ne 2782  df-ral 2901  df-rex 2902  df-reu 2903  df-rab 2905  df-v 3175  df-sbc 3403  df-csb 3500  df-dif 3543  df-un 3545  df-in 3547  df-ss 3554  df-nul 3875  df-if 4037  df-sn 4126  df-pr 4128  df-op 4132  df-uni 4373  df-iun 4457  df-br 4584  df-opab 4644  df-mpt 4645  df-id 4953  df-xp 5044  df-rel 5045  df-cnv 5046  df-co 5047  df-dm 5048  df-rn 5049  df-res 5050  df-ima 5051  df-iota 5768  df-fun 5806  df-fn 5807  df-f 5808  df-f1 5809  df-fo 5810  df-f1o 5811  df-fv 5812  df-riota 6511  df-ov 6552  df-oprab 6553  df-mpt2 6554  df-slot 15699  df-base 15700  df-ress 15702  df-minusg 17249  df-invr 18495

This theorem is referenced by:  unitinvcl  18497  unitinvinv  18498  unitlinv  18500  unitrinv  18501  invrpropd  18521  subrgugrp  18622  cnmsubglem  19628  psgninv  19747  invrvald  20301  invrcn2  21793  nrginvrcn  22306  nrgtdrg  22307  sum2dchr  24799  rdivmuldivd  29122  ringinvval  29123  dvrcan5  29124  cntzsdrg  36791