Theorem grpissubg 17437

Description: If the base set of a group is contained in the base set of another group, and the group operation of the group is the restriction of the group operation of the other group to its base set, then the (base set of the) group is subgroup of the other group. (Contributed by AV, 14-Mar-2019.)

Hypotheses

Ref	Expression
grpissubg.b	⊢ 𝐵 = (Base‘𝐺)
grpissubg.s	⊢ 𝑆 = (Base‘𝐻)

Assertion

Ref	Expression
grpissubg	⊢ ((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) → ((𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆))) → 𝑆 ∈ (SubGrp‘𝐺)))

Proof of Theorem grpissubg

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

Step	Hyp	Ref	Expression
1		simpl 472	. . . 4 ⊢ ((𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆))) → 𝑆 ⊆ 𝐵)
2	1	adantl 481	. . 3 ⊢ (((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) → 𝑆 ⊆ 𝐵)
3		grpissubg.s	. . . . 5 ⊢ 𝑆 = (Base‘𝐻)
4	3	grpbn0 17274	. . . 4 ⊢ (𝐻 ∈ Grp → 𝑆 ≠ ∅)
5	4	ad2antlr 759	. . 3 ⊢ (((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) → 𝑆 ≠ ∅)
6		ovres 6698	. . . . . . . 8 ⊢ ((𝑎 ∈ 𝑆 ∧ 𝑏 ∈ 𝑆) → (𝑎((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑏) = (𝑎(+g‘𝐺)𝑏))
7	6	adantll 746	. . . . . . 7 ⊢ (((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) ∧ 𝑏 ∈ 𝑆) → (𝑎((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑏) = (𝑎(+g‘𝐺)𝑏))
8		simplr 788	. . . . . . . . . 10 ⊢ (((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) → 𝐻 ∈ Grp)
9	8	ad2antrr 758	. . . . . . . . 9 ⊢ (((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) ∧ 𝑏 ∈ 𝑆) → 𝐻 ∈ Grp)
10		simplr 788	. . . . . . . . 9 ⊢ (((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) ∧ 𝑏 ∈ 𝑆) → 𝑎 ∈ 𝑆)
11		simpr 476	. . . . . . . . 9 ⊢ (((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) ∧ 𝑏 ∈ 𝑆) → 𝑏 ∈ 𝑆)
12		eqid 2610	. . . . . . . . . 10 ⊢ (+g‘𝐻) = (+g‘𝐻)
13	3, 12	grpcl 17253	. . . . . . . . 9 ⊢ ((𝐻 ∈ Grp ∧ 𝑎 ∈ 𝑆 ∧ 𝑏 ∈ 𝑆) → (𝑎(+g‘𝐻)𝑏) ∈ 𝑆)
14	9, 10, 11, 13	syl3anc 1318	. . . . . . . 8 ⊢ (((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) ∧ 𝑏 ∈ 𝑆) → (𝑎(+g‘𝐻)𝑏) ∈ 𝑆)
15		oveq 6555	. . . . . . . . . . . . 13 ⊢ ((+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)) → (𝑎(+g‘𝐻)𝑏) = (𝑎((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑏))
16	15	eqcomd 2616	. . . . . . . . . . . 12 ⊢ ((+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)) → (𝑎((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑏) = (𝑎(+g‘𝐻)𝑏))
17	16	eleq1d 2672	. . . . . . . . . . 11 ⊢ ((+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)) → ((𝑎((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑏) ∈ 𝑆 ↔ (𝑎(+g‘𝐻)𝑏) ∈ 𝑆))
18	17	adantl 481	. . . . . . . . . 10 ⊢ ((𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆))) → ((𝑎((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑏) ∈ 𝑆 ↔ (𝑎(+g‘𝐻)𝑏) ∈ 𝑆))
19	18	adantl 481	. . . . . . . . 9 ⊢ (((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) → ((𝑎((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑏) ∈ 𝑆 ↔ (𝑎(+g‘𝐻)𝑏) ∈ 𝑆))
20	19	ad2antrr 758	. . . . . . . 8 ⊢ (((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) ∧ 𝑏 ∈ 𝑆) → ((𝑎((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑏) ∈ 𝑆 ↔ (𝑎(+g‘𝐻)𝑏) ∈ 𝑆))
21	14, 20	mpbird 246	. . . . . . 7 ⊢ (((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) ∧ 𝑏 ∈ 𝑆) → (𝑎((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑏) ∈ 𝑆)
22	7, 21	eqeltrrd 2689	. . . . . 6 ⊢ (((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) ∧ 𝑏 ∈ 𝑆) → (𝑎(+g‘𝐺)𝑏) ∈ 𝑆)
23	22	ralrimiva 2949	. . . . 5 ⊢ ((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) → ∀𝑏 ∈ 𝑆 (𝑎(+g‘𝐺)𝑏) ∈ 𝑆)
24		simpl 472	. . . . . . . . 9 ⊢ ((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) → 𝐺 ∈ Grp)
25	24	adantr 480	. . . . . . . 8 ⊢ (((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) → 𝐺 ∈ Grp)
26		grpissubg.b	. . . . . . . . . . . 12 ⊢ 𝐵 = (Base‘𝐺)
27	26	sseq2i 3593	. . . . . . . . . . 11 ⊢ (𝑆 ⊆ 𝐵 ↔ 𝑆 ⊆ (Base‘𝐺))
28	27	biimpi 205	. . . . . . . . . 10 ⊢ (𝑆 ⊆ 𝐵 → 𝑆 ⊆ (Base‘𝐺))
29	28	adantr 480	. . . . . . . . 9 ⊢ ((𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆))) → 𝑆 ⊆ (Base‘𝐺))
30	29	adantl 481	. . . . . . . 8 ⊢ (((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) → 𝑆 ⊆ (Base‘𝐺))
31		ovres 6698	. . . . . . . . . . 11 ⊢ ((𝑥 ∈ 𝑆 ∧ 𝑦 ∈ 𝑆) → (𝑥((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑦) = (𝑥(+g‘𝐺)𝑦))
32	31	adantl 481	. . . . . . . . . 10 ⊢ ((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ (𝑥 ∈ 𝑆 ∧ 𝑦 ∈ 𝑆)) → (𝑥((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑦) = (𝑥(+g‘𝐺)𝑦))
33		oveq 6555	. . . . . . . . . . . . 13 ⊢ ((+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)) → (𝑥(+g‘𝐻)𝑦) = (𝑥((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑦))
34	33	adantl 481	. . . . . . . . . . . 12 ⊢ ((𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆))) → (𝑥(+g‘𝐻)𝑦) = (𝑥((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑦))
35	34	eqcomd 2616	. . . . . . . . . . 11 ⊢ ((𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆))) → (𝑥((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑦) = (𝑥(+g‘𝐻)𝑦))
36	35	ad2antlr 759	. . . . . . . . . 10 ⊢ ((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ (𝑥 ∈ 𝑆 ∧ 𝑦 ∈ 𝑆)) → (𝑥((+g‘𝐺) ↾ (𝑆 × 𝑆))𝑦) = (𝑥(+g‘𝐻)𝑦))
37	32, 36	eqtr3d 2646	. . . . . . . . 9 ⊢ ((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ (𝑥 ∈ 𝑆 ∧ 𝑦 ∈ 𝑆)) → (𝑥(+g‘𝐺)𝑦) = (𝑥(+g‘𝐻)𝑦))
38	37	ralrimivva 2954	. . . . . . . 8 ⊢ (((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) → ∀𝑥 ∈ 𝑆 ∀𝑦 ∈ 𝑆 (𝑥(+g‘𝐺)𝑦) = (𝑥(+g‘𝐻)𝑦))
39	25, 8, 3, 30, 38	grpinvssd 17315	. . . . . . 7 ⊢ (((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) → (𝑎 ∈ 𝑆 → ((invg‘𝐻)‘𝑎) = ((invg‘𝐺)‘𝑎)))
40	39	imp 444	. . . . . 6 ⊢ ((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) → ((invg‘𝐻)‘𝑎) = ((invg‘𝐺)‘𝑎))
41		eqid 2610	. . . . . . . . . 10 ⊢ (invg‘𝐻) = (invg‘𝐻)
42	3, 41	grpinvcl 17290	. . . . . . . . 9 ⊢ ((𝐻 ∈ Grp ∧ 𝑎 ∈ 𝑆) → ((invg‘𝐻)‘𝑎) ∈ 𝑆)
43	42	ex 449	. . . . . . . 8 ⊢ (𝐻 ∈ Grp → (𝑎 ∈ 𝑆 → ((invg‘𝐻)‘𝑎) ∈ 𝑆))
44	43	ad2antlr 759	. . . . . . 7 ⊢ (((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) → (𝑎 ∈ 𝑆 → ((invg‘𝐻)‘𝑎) ∈ 𝑆))
45	44	imp 444	. . . . . 6 ⊢ ((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) → ((invg‘𝐻)‘𝑎) ∈ 𝑆)
46	40, 45	eqeltrrd 2689	. . . . 5 ⊢ ((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) → ((invg‘𝐺)‘𝑎) ∈ 𝑆)
47	23, 46	jca 553	. . . 4 ⊢ ((((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) ∧ 𝑎 ∈ 𝑆) → (∀𝑏 ∈ 𝑆 (𝑎(+g‘𝐺)𝑏) ∈ 𝑆 ∧ ((invg‘𝐺)‘𝑎) ∈ 𝑆))
48	47	ralrimiva 2949	. . 3 ⊢ (((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) → ∀𝑎 ∈ 𝑆 (∀𝑏 ∈ 𝑆 (𝑎(+g‘𝐺)𝑏) ∈ 𝑆 ∧ ((invg‘𝐺)‘𝑎) ∈ 𝑆))
49		eqid 2610	. . . . 5 ⊢ (+g‘𝐺) = (+g‘𝐺)
50		eqid 2610	. . . . 5 ⊢ (invg‘𝐺) = (invg‘𝐺)
51	26, 49, 50	issubg2 17432	. . . 4 ⊢ (𝐺 ∈ Grp → (𝑆 ∈ (SubGrp‘𝐺) ↔ (𝑆 ⊆ 𝐵 ∧ 𝑆 ≠ ∅ ∧ ∀𝑎 ∈ 𝑆 (∀𝑏 ∈ 𝑆 (𝑎(+g‘𝐺)𝑏) ∈ 𝑆 ∧ ((invg‘𝐺)‘𝑎) ∈ 𝑆))))
52	51	ad2antrr 758	. . 3 ⊢ (((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) → (𝑆 ∈ (SubGrp‘𝐺) ↔ (𝑆 ⊆ 𝐵 ∧ 𝑆 ≠ ∅ ∧ ∀𝑎 ∈ 𝑆 (∀𝑏 ∈ 𝑆 (𝑎(+g‘𝐺)𝑏) ∈ 𝑆 ∧ ((invg‘𝐺)‘𝑎) ∈ 𝑆))))
53	2, 5, 48, 52	mpbir3and 1238	. 2 ⊢ (((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) ∧ (𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆)))) → 𝑆 ∈ (SubGrp‘𝐺))
54	53	ex 449	1 ⊢ ((𝐺 ∈ Grp ∧ 𝐻 ∈ Grp) → ((𝑆 ⊆ 𝐵 ∧ (+g‘𝐻) = ((+g‘𝐺) ↾ (𝑆 × 𝑆))) → 𝑆 ∈ (SubGrp‘𝐺)))

Syntax hints:   → wi 4   ↔ wb 195   ∧ wa 383   ∧ w3a 1031   = wceq 1475   ∈ wcel 1977   ≠ wne 2780  ∀wral 2896   ⊆ wss 3540  ∅c0 3874   × cxp 5036   ↾ cres 5040  ‘cfv 5804  (class class class)co 6549  Basecbs 15695  +_gcplusg 15768  Grpcgrp 17245  inv_gcminusg 17246  SubGrpcsubg 17411

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  ax-un 6847  ax-cnex 9871  ax-resscn 9872  ax-1cn 9873  ax-icn 9874  ax-addcl 9875  ax-addrcl 9876  ax-mulcl 9877  ax-mulrcl 9878  ax-mulcom 9879  ax-addass 9880  ax-mulass 9881  ax-distr 9882  ax-i2m1 9883  ax-1ne0 9884  ax-1rid 9885  ax-rnegex 9886  ax-rrecex 9887  ax-cnre 9888  ax-pre-lttri 9889  ax-pre-lttrn 9890  ax-pre-ltadd 9891  ax-pre-mulgt0 9892

This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-3or 1032  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-nel 2783  df-ral 2901  df-rex 2902  df-reu 2903  df-rmo 2904  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-pss 3556  df-nul 3875  df-if 4037  df-pw 4110  df-sn 4126  df-pr 4128  df-tp 4130  df-op 4132  df-uni 4373  df-iun 4457  df-br 4584  df-opab 4644  df-mpt 4645  df-tr 4681  df-eprel 4949  df-id 4953  df-po 4959  df-so 4960  df-fr 4997  df-we 4999  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-pred 5597  df-ord 5643  df-on 5644  df-lim 5645  df-suc 5646  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-om 6958  df-wrecs 7294  df-recs 7355  df-rdg 7393  df-er 7629  df-en 7842  df-dom 7843  df-sdom 7844  df-pnf 9955  df-mnf 9956  df-xr 9957  df-ltxr 9958  df-le 9959  df-sub 10147  df-neg 10148  df-nn 10898  df-2 10956  df-ndx 15698  df-slot 15699  df-base 15700  df-sets 15701  df-ress 15702  df-plusg 15781  df-0g 15925  df-mgm 17065  df-sgrp 17107  df-mnd 17118  df-grp 17248  df-minusg 17249  df-subg 17414

This theorem is referenced by:  resgrpisgrp  17438  pgrpsubgsymg  17651