Theorem crngunit 14256

Description: Property of being a unit in a commutative ring. (Contributed by Mario Carneiro, 18-Apr-2016.)

Hypotheses

Ref	Expression
crngunit.1	|- U = (Unit ` R )
crngunit.2	|- .1. = ( 1r ` R )
crngunit.3	|- .|| = ( ||r ` R )

Assertion

Ref	Expression
crngunit	|- ( R e. CRing -> ( X e. U <-> X .|| .1. ) )

Proof of Theorem crngunit

Dummy variable y is distinct from all other variables.

Step	Hyp	Ref	Expression
1		crngunit.1	. . . . 5 |- U = (Unit ` R )
2	1	a1i 9	. . . 4 |- ( R e. CRing -> U = (Unit ` R ) )
3		crngunit.2	. . . . 5 |- .1. = ( 1r ` R )
4	3	a1i 9	. . . 4 |- ( R e. CRing -> .1. = ( 1r ` R ) )
5		crngunit.3	. . . . 5 |- .|| = ( ||r ` R )
6	5	a1i 9	. . . 4 |- ( R e. CRing -> .|| = ( ||r ` R ) )
7		eqidd 2233	. . . 4 |- ( R e. CRing -> (oppr ` R ) = (oppr ` R ) )
8		eqidd 2233	. . . 4 |- ( R e. CRing -> ( ||r ` (oppr ` R ) ) = ( ||r ` (oppr ` R ) ) )
9		crngring 14152	. . . . 5 |- ( R e. CRing -> R e. Ring )
10		ringsrg 14191	. . . . 5 |- ( R e. Ring -> R e. SRing )
11	9, 10	syl 14	. . . 4 |- ( R e. CRing -> R e. SRing )
12	2, 4, 6, 7, 8, 11	isunitd 14251	. . 3 |- ( R e. CRing -> ( X e. U <-> ( X .|| .1. /\ X ( ||r ` (oppr ` R ) ) .1. ) ) )
13		eqid 2232	. . . . . . . . . . . 12 |- ( Base ` R ) = ( Base ` R )
14		eqid 2232	. . . . . . . . . . . 12 |- ( .r ` R ) = ( .r ` R )
15		eqid 2232	. . . . . . . . . . . 12 |- (oppr ` R ) = (oppr ` R )
16		eqid 2232	. . . . . . . . . . . 12 |- ( .r ` (oppr ` R ) ) = ( .r ` (oppr ` R ) )
17	13, 14, 15, 16	crngoppr 14216	. . . . . . . . . . 11 |- ( ( R e. CRing /\ y e. ( Base ` R ) /\ X e. ( Base ` R ) ) -> ( y ( .r ` R ) X ) = ( y ( .r ` (oppr ` R ) ) X ) )
18	17	3expa 1230	. . . . . . . . . 10 |- ( ( ( R e. CRing /\ y e. ( Base ` R ) ) /\ X e. ( Base ` R ) ) -> ( y ( .r ` R ) X ) = ( y ( .r ` (oppr ` R ) ) X ) )
19	18	eqcomd 2238	. . . . . . . . 9 |- ( ( ( R e. CRing /\ y e. ( Base ` R ) ) /\ X e. ( Base ` R ) ) -> ( y ( .r ` (oppr ` R ) ) X ) = ( y ( .r ` R ) X ) )
20	19	an32s 570	. . . . . . . 8 |- ( ( ( R e. CRing /\ X e. ( Base ` R ) ) /\ y e. ( Base ` R ) ) -> ( y ( .r ` (oppr ` R ) ) X ) = ( y ( .r ` R ) X ) )
21	20	eqeq1d 2241	. . . . . . 7 |- ( ( ( R e. CRing /\ X e. ( Base ` R ) ) /\ y e. ( Base ` R ) ) -> ( ( y ( .r ` (oppr ` R ) ) X ) = .1. <-> ( y ( .r ` R ) X ) = .1. ) )
22	21	rexbidva 2539	. . . . . 6 |- ( ( R e. CRing /\ X e. ( Base ` R ) ) -> ( E. y e. ( Base ` R ) ( y ( .r ` (oppr ` R ) ) X ) = .1. <-> E. y e. ( Base ` R ) ( y ( .r ` R ) X ) = .1. ) )
23	22	pm5.32da 452	. . . . 5 |- ( R e. CRing -> ( ( X e. ( Base ` R ) /\ E. y e. ( Base ` R ) ( y ( .r ` (oppr ` R ) ) X ) = .1. ) <-> ( X e. ( Base ` R ) /\ E. y e. ( Base ` R ) ( y ( .r ` R ) X ) = .1. ) ) )
24	15, 13	opprbasg 14219	. . . . . 6 |- ( R e. CRing -> ( Base ` R ) = ( Base ` (oppr ` R ) ) )
25	15	opprring 14223	. . . . . . 7 |- ( R e. Ring -> (oppr ` R ) e. Ring )
26		ringsrg 14191	. . . . . . 7 |- ( (oppr ` R ) e. Ring -> (oppr ` R ) e. SRing )
27	9, 25, 26	3syl 17	. . . . . 6 |- ( R e. CRing -> (oppr ` R ) e. SRing )
28		eqidd 2233	. . . . . 6 |- ( R e. CRing -> ( .r ` (oppr ` R ) ) = ( .r ` (oppr ` R ) ) )
29	24, 8, 27, 28	dvdsrd 14239	. . . . 5 |- ( R e. CRing -> ( X ( ||r ` (oppr ` R ) ) .1. <-> ( X e. ( Base ` R ) /\ E. y e. ( Base ` R ) ( y ( .r ` (oppr ` R ) ) X ) = .1. ) ) )
30		eqidd 2233	. . . . . 6 |- ( R e. CRing -> ( Base ` R ) = ( Base ` R ) )
31		eqidd 2233	. . . . . 6 |- ( R e. CRing -> ( .r ` R ) = ( .r ` R ) )
32	30, 6, 11, 31	dvdsrd 14239	. . . . 5 |- ( R e. CRing -> ( X .|| .1. <-> ( X e. ( Base ` R ) /\ E. y e. ( Base ` R ) ( y ( .r ` R ) X ) = .1. ) ) )
33	23, 29, 32	3bitr4d 220	. . . 4 |- ( R e. CRing -> ( X ( ||r ` (oppr ` R ) ) .1. <-> X .|| .1. ) )
34	33	anbi2d 464	. . 3 |- ( R e. CRing -> ( ( X .|| .1. /\ X ( ||r ` (oppr ` R ) ) .1. ) <-> ( X .|| .1. /\ X .|| .1. ) ) )
35	12, 34	bitrd 188	. 2 |- ( R e. CRing -> ( X e. U <-> ( X .|| .1. /\ X .|| .1. ) ) )
36		pm4.24 395	. 2 |- ( X .|| .1. <-> ( X .|| .1. /\ X .|| .1. ) )
37	35, 36	bitr4di 198	1 |- ( R e. CRing -> ( X e. U <-> X .|| .1. ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1398   e. wcel 2203   E.wrex 2521   class class class wbr 4109   ` cfv 5352  (class class class)co 6050   Basecbs 13212   .rcmulr 13291   1rcur 14103  SRingcsrg 14107   Ringcrg 14140   CRingccrg 14141  opp_rcoppr 14211   ||_rcdsr 14230  Unitcui 14231

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 619  ax-in2 620  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2205  ax-14 2206  ax-ext 2214  ax-coll 4225  ax-sep 4228  ax-nul 4236  ax-pow 4287  ax-pr 4322  ax-un 4554  ax-setind 4659  ax-cnex 8218  ax-resscn 8219  ax-1cn 8220  ax-1re 8221  ax-icn 8222  ax-addcl 8223  ax-addrcl 8224  ax-mulcl 8225  ax-addcom 8227  ax-addass 8229  ax-i2m1 8232  ax-0lt1 8233  ax-0id 8235  ax-rnegex 8236  ax-pre-ltirr 8239  ax-pre-lttrn 8241  ax-pre-ltadd 8243

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-fal 1404  df-nf 1510  df-sb 1812  df-eu 2083  df-mo 2084  df-clab 2219  df-cleq 2225  df-clel 2228  df-nfc 2373  df-ne 2413  df-nel 2508  df-ral 2525  df-rex 2526  df-reu 2527  df-rmo 2528  df-rab 2529  df-v 2815  df-sbc 3043  df-csb 3139  df-dif 3213  df-un 3215  df-in 3217  df-ss 3224  df-nul 3509  df-pw 3671  df-sn 3695  df-pr 3696  df-op 3698  df-uni 3915  df-int 3950  df-iun 3993  df-br 4110  df-opab 4172  df-mpt 4173  df-id 4414  df-xp 4755  df-rel 4756  df-cnv 4757  df-co 4758  df-dm 4759  df-rn 4760  df-res 4761  df-ima 4762  df-iota 5312  df-fun 5354  df-fn 5355  df-f 5356  df-f1 5357  df-fo 5358  df-f1o 5359  df-fv 5360  df-riota 6003  df-ov 6053  df-oprab 6054  df-mpo 6055  df-tpos 6476  df-pnf 8310  df-mnf 8311  df-ltxr 8313  df-inn 9238  df-2 9296  df-3 9297  df-ndx 13215  df-slot 13216  df-base 13218  df-sets 13219  df-plusg 13303  df-mulr 13304  df-0g 13471  df-mgm 13569  df-sgrp 13615  df-mnd 13630  df-grp 13716  df-minusg 13717  df-cmn 14003  df-abl 14004  df-mgp 14065  df-ur 14104  df-srg 14108  df-ring 14142  df-cring 14143  df-oppr 14212  df-dvdsr 14233  df-unit 14234

This theorem is referenced by:  dvdsunit  14257  cnfldui  14737  znunit  14807