Theorem ringressid 14042

Description: A ring restricted to its base set is a ring. It will usually be the original ring exactly, of course, but to show that needs additional conditions such as those in strressid 13120. (Contributed by Jim Kingdon, 28-Feb-2025.)

Hypothesis

Ref	Expression
ringressid.b	|- B = ( Base ` G )

Assertion

Ref	Expression
ringressid	|- ( G e. Ring -> ( G ↾s B ) e. Ring )

Proof of Theorem ringressid

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

Step	Hyp	Ref	Expression
1		eqidd 2230	. . 3 |- ( G e. Ring -> ( G ↾s B ) = ( G ↾s B ) )
2		ringressid.b	. . . 4 |- B = ( Base ` G )
3	2	a1i 9	. . 3 |- ( G e. Ring -> B = ( Base ` G ) )
4		id 19	. . 3 |- ( G e. Ring -> G e. Ring )
5		ssidd 3245	. . 3 |- ( G e. Ring -> B C_ B )
6	1, 3, 4, 5	ressbas2d 13117	. 2 |- ( G e. Ring -> B = ( Base ` ( G ↾s B ) ) )
7		eqidd 2230	. . 3 |- ( G e. Ring -> ( +g ` G ) = ( +g ` G ) )
8		basfn 13107	. . . . 5 |- Base Fn _V
9		elex 2811	. . . . 5 |- ( G e. Ring -> G e. _V )
10		funfvex 5646	. . . . . 6 |- ( ( Fun Base /\ G e. dom Base ) -> ( Base ` G ) e. _V )
11	10	funfni 5423	. . . . 5 |- ( ( Base Fn _V /\ G e. _V ) -> ( Base ` G ) e. _V )
12	8, 9, 11	sylancr 414	. . . 4 |- ( G e. Ring -> ( Base ` G ) e. _V )
13	2, 12	eqeltrid 2316	. . 3 |- ( G e. Ring -> B e. _V )
14	1, 7, 13, 4	ressplusgd 13178	. 2 |- ( G e. Ring -> ( +g ` G ) = ( +g ` ( G ↾s B ) ) )
15		eqid 2229	. . . 4 |- ( G ↾s B ) = ( G ↾s B )
16		eqid 2229	. . . 4 |- ( .r ` G ) = ( .r ` G )
17	15, 16	ressmulrg 13194	. . 3 |- ( ( B e. _V /\ G e. Ring ) -> ( .r ` G ) = ( .r ` ( G ↾s B ) ) )
18	13, 17	mpancom 422	. 2 |- ( G e. Ring -> ( .r ` G ) = ( .r ` ( G ↾s B ) ) )
19		ringgrp 13980	. . 3 |- ( G e. Ring -> G e. Grp )
20	2	grpressid 13610	. . 3 |- ( G e. Grp -> ( G ↾s B ) e. Grp )
21	19, 20	syl 14	. 2 |- ( G e. Ring -> ( G ↾s B ) e. Grp )
22	2, 16	ringcl 13992	. 2 |- ( ( G e. Ring /\ x e. B /\ y e. B ) -> ( x ( .r ` G ) y ) e. B )
23	2, 16	ringass 13995	. 2 |- ( ( G e. Ring /\ ( x e. B /\ y e. B /\ z e. B ) ) -> ( ( x ( .r ` G ) y ) ( .r ` G ) z ) = ( x ( .r ` G ) ( y ( .r ` G ) z ) ) )
24		eqid 2229	. . 3 |- ( +g ` G ) = ( +g ` G )
25	2, 24, 16	ringdi 13997	. 2 |- ( ( G e. Ring /\ ( x e. B /\ y e. B /\ z e. B ) ) -> ( x ( .r ` G ) ( y ( +g ` G ) z ) ) = ( ( x ( .r ` G ) y ) ( +g ` G ) ( x ( .r ` G ) z ) ) )
26	2, 24, 16	ringdir 13998	. 2 |- ( ( G e. Ring /\ ( x e. B /\ y e. B /\ z e. B ) ) -> ( ( x ( +g ` G ) y ) ( .r ` G ) z ) = ( ( x ( .r ` G ) z ) ( +g ` G ) ( y ( .r ` G ) z ) ) )
27		eqid 2229	. . 3 |- ( 1r ` G ) = ( 1r ` G )
28	2, 27	ringidcl 13999	. 2 |- ( G e. Ring -> ( 1r ` G ) e. B )
29	2, 16, 27	ringlidm 14002	. 2 |- ( ( G e. Ring /\ x e. B ) -> ( ( 1r ` G ) ( .r ` G ) x ) = x )
30	2, 16, 27	ringridm 14003	. 2 |- ( ( G e. Ring /\ x e. B ) -> ( x ( .r ` G ) ( 1r ` G ) ) = x )
31	6, 14, 18, 21, 22, 23, 25, 26, 28, 29, 30	isringd 14020	1 |- ( G e. Ring -> ( G ↾s B ) e. Ring )

Syntax hints:   -> wi 4   = wceq 1395   e. wcel 2200   _Vcvv 2799   Fn wfn 5313   ` cfv 5318  (class class class)co 6007   Basecbs 13048   ↾_s cress 13049   +g cplusg 13126   .rcmulr 13127   Grpcgrp 13549   1rcur 13938   Ringcrg 13975

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 617  ax-in2 618  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-13 2202  ax-14 2203  ax-ext 2211  ax-coll 4199  ax-sep 4202  ax-pow 4258  ax-pr 4293  ax-un 4524  ax-setind 4629  ax-cnex 8101  ax-resscn 8102  ax-1cn 8103  ax-1re 8104  ax-icn 8105  ax-addcl 8106  ax-addrcl 8107  ax-mulcl 8108  ax-addcom 8110  ax-addass 8112  ax-i2m1 8115  ax-0lt1 8116  ax-0id 8118  ax-rnegex 8119  ax-pre-ltirr 8122  ax-pre-lttrn 8124  ax-pre-ltadd 8126

This theorem depends on definitions:  df-bi 117  df-3an 1004  df-tru 1398  df-fal 1401  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-ne 2401  df-nel 2496  df-ral 2513  df-rex 2514  df-reu 2515  df-rmo 2516  df-rab 2517  df-v 2801  df-sbc 3029  df-csb 3125  df-dif 3199  df-un 3201  df-in 3203  df-ss 3210  df-nul 3492  df-pw 3651  df-sn 3672  df-pr 3673  df-op 3675  df-uni 3889  df-int 3924  df-iun 3967  df-br 4084  df-opab 4146  df-mpt 4147  df-id 4384  df-xp 4725  df-rel 4726  df-cnv 4727  df-co 4728  df-dm 4729  df-rn 4730  df-res 4731  df-ima 4732  df-iota 5278  df-fun 5320  df-fn 5321  df-f 5322  df-f1 5323  df-fo 5324  df-f1o 5325  df-fv 5326  df-riota 5960  df-ov 6010  df-oprab 6011  df-mpo 6012  df-pnf 8194  df-mnf 8195  df-ltxr 8197  df-inn 9122  df-2 9180  df-3 9181  df-ndx 13051  df-slot 13052  df-base 13054  df-sets 13055  df-iress 13056  df-plusg 13139  df-mulr 13140  df-0g 13307  df-mgm 13405  df-sgrp 13451  df-mnd 13466  df-grp 13552  df-minusg 13553  df-mgp 13900  df-ur 13939  df-ring 13977

This theorem is referenced by:  subrgid  14203