Metamath Proof Explorer


Theorem quslsm

Description: Express the image by the quotient map in terms of direct sum. (Contributed by Thierry Arnoux, 27-Jul-2024)

Ref Expression
Hypotheses quslsm.b ⊢ B = Base G
quslsm.p ⊢ ⊕ ˙ = LSSum ⁡ G
quslsm.n ⊢ φ → S ∈ SubGrp ⁡ G
quslsm.s ⊢ φ → X ∈ B
Assertion quslsm ⊢ φ → X G ~ QG S = X ⊕ ˙ S

Proof

Step Hyp Ref Expression
1 quslsm.b ⊢ B = Base G
2 quslsm.p ⊢ ⊕ ˙ = LSSum ⁡ G
3 quslsm.n ⊢ φ → S ∈ SubGrp ⁡ G
4 quslsm.s ⊢ φ → X ∈ B
5 subgrcl ⊢ S ∈ SubGrp ⁡ G → G ∈ Grp
6 3 5 syl ⊢ φ → G ∈ Grp
7 1 subgss ⊢ S ∈ SubGrp ⁡ G → S ⊆ B
8 3 7 syl ⊢ φ → S ⊆ B
9 eqid ⊢ inv g ⁡ G = inv g ⁡ G
10 eqid ⊢ + G = + G
11 eqid ⊢ G ~ QG S = G ~ QG S
12 1 9 10 11 eqgfval ⊢ G ∈ Grp ∧ S ⊆ B → G ~ QG S = i j | i j ⊆ B ∧ inv g ⁡ G ⁡ i + G j ∈ S
13 6 8 12 syl2anc ⊢ φ → G ~ QG S = i j | i j ⊆ B ∧ inv g ⁡ G ⁡ i + G j ∈ S
14 simpr ⊢ φ ∧ i j ⊆ B ∧ inv g ⁡ G ⁡ i + G j ∈ S → inv g ⁡ G ⁡ i + G j ∈ S
15 oveq2 ⊢ k = inv g ⁡ G ⁡ i + G j → i + G k = i + G inv g ⁡ G ⁡ i + G j
16 15 eqeq1d ⊢ k = inv g ⁡ G ⁡ i + G j → i + G k = j ↔ i + G inv g ⁡ G ⁡ i + G j = j
17 16 adantl ⊢ φ ∧ i j ⊆ B ∧ inv g ⁡ G ⁡ i + G j ∈ S ∧ k = inv g ⁡ G ⁡ i + G j → i + G k = j ↔ i + G inv g ⁡ G ⁡ i + G j = j
18 6 adantr ⊢ φ ∧ i j ⊆ B → G ∈ Grp
19 vex ⊢ i ∈ V
20 vex ⊢ j ∈ V
21 19 20 prss ⊢ i ∈ B ∧ j ∈ B ↔ i j ⊆ B
22 21 bicomi ⊢ i j ⊆ B ↔ i ∈ B ∧ j ∈ B
23 22 simplbi ⊢ i j ⊆ B → i ∈ B
24 23 adantl ⊢ φ ∧ i j ⊆ B → i ∈ B
25 eqid ⊢ 0 G = 0 G
26 1 10 25 9 grprinv ⊢ G ∈ Grp ∧ i ∈ B → i + G inv g ⁡ G ⁡ i = 0 G
27 18 24 26 syl2anc ⊢ φ ∧ i j ⊆ B → i + G inv g ⁡ G ⁡ i = 0 G
28 27 oveq1d ⊢ φ ∧ i j ⊆ B → i + G inv g ⁡ G ⁡ i + G j = 0 G + G j
29 1 9 grpinvcl ⊢ G ∈ Grp ∧ i ∈ B → inv g ⁡ G ⁡ i ∈ B
30 18 24 29 syl2anc ⊢ φ ∧ i j ⊆ B → inv g ⁡ G ⁡ i ∈ B
31 22 simprbi ⊢ i j ⊆ B → j ∈ B
32 31 adantl ⊢ φ ∧ i j ⊆ B → j ∈ B
33 1 10 grpass ⊢ G ∈ Grp ∧ i ∈ B ∧ inv g ⁡ G ⁡ i ∈ B ∧ j ∈ B → i + G inv g ⁡ G ⁡ i + G j = i + G inv g ⁡ G ⁡ i + G j
34 18 24 30 32 33 syl13anc ⊢ φ ∧ i j ⊆ B → i + G inv g ⁡ G ⁡ i + G j = i + G inv g ⁡ G ⁡ i + G j
35 1 10 25 grplid ⊢ G ∈ Grp ∧ j ∈ B → 0 G + G j = j
36 18 32 35 syl2anc ⊢ φ ∧ i j ⊆ B → 0 G + G j = j
37 28 34 36 3eqtr3d ⊢ φ ∧ i j ⊆ B → i + G inv g ⁡ G ⁡ i + G j = j
38 37 adantr ⊢ φ ∧ i j ⊆ B ∧ inv g ⁡ G ⁡ i + G j ∈ S → i + G inv g ⁡ G ⁡ i + G j = j
39 14 17 38 rspcedvd ⊢ φ ∧ i j ⊆ B ∧ inv g ⁡ G ⁡ i + G j ∈ S → ∃ k ∈ S i + G k = j
40 oveq2 ⊢ i + G k = j → inv g ⁡ G ⁡ i + G i + G k = inv g ⁡ G ⁡ i + G j
41 40 adantl ⊢ φ ∧ i j ⊆ B ∧ k ∈ S ∧ i + G k = j → inv g ⁡ G ⁡ i + G i + G k = inv g ⁡ G ⁡ i + G j
42 simpll ⊢ φ ∧ i j ⊆ B ∧ k ∈ S → φ
43 24 adantr ⊢ φ ∧ i j ⊆ B ∧ k ∈ S → i ∈ B
44 8 adantr ⊢ φ ∧ i j ⊆ B → S ⊆ B
45 44 sselda ⊢ φ ∧ i j ⊆ B ∧ k ∈ S → k ∈ B
46 6 3ad2ant1 ⊢ φ ∧ i ∈ B ∧ k ∈ B → G ∈ Grp
47 simp2 ⊢ φ ∧ i ∈ B ∧ k ∈ B → i ∈ B
48 1 10 25 9 grplinv ⊢ G ∈ Grp ∧ i ∈ B → inv g ⁡ G ⁡ i + G i = 0 G
49 46 47 48 syl2anc ⊢ φ ∧ i ∈ B ∧ k ∈ B → inv g ⁡ G ⁡ i + G i = 0 G
50 49 oveq1d ⊢ φ ∧ i ∈ B ∧ k ∈ B → inv g ⁡ G ⁡ i + G i + G k = 0 G + G k
51 46 47 29 syl2anc ⊢ φ ∧ i ∈ B ∧ k ∈ B → inv g ⁡ G ⁡ i ∈ B
52 simp3 ⊢ φ ∧ i ∈ B ∧ k ∈ B → k ∈ B
53 1 10 grpass ⊢ G ∈ Grp ∧ inv g ⁡ G ⁡ i ∈ B ∧ i ∈ B ∧ k ∈ B → inv g ⁡ G ⁡ i + G i + G k = inv g ⁡ G ⁡ i + G i + G k
54 46 51 47 52 53 syl13anc ⊢ φ ∧ i ∈ B ∧ k ∈ B → inv g ⁡ G ⁡ i + G i + G k = inv g ⁡ G ⁡ i + G i + G k
55 1 10 25 grplid ⊢ G ∈ Grp ∧ k ∈ B → 0 G + G k = k
56 46 52 55 syl2anc ⊢ φ ∧ i ∈ B ∧ k ∈ B → 0 G + G k = k
57 50 54 56 3eqtr3d ⊢ φ ∧ i ∈ B ∧ k ∈ B → inv g ⁡ G ⁡ i + G i + G k = k
58 42 43 45 57 syl3anc ⊢ φ ∧ i j ⊆ B ∧ k ∈ S → inv g ⁡ G ⁡ i + G i + G k = k
59 58 adantr ⊢ φ ∧ i j ⊆ B ∧ k ∈ S ∧ i + G k = j → inv g ⁡ G ⁡ i + G i + G k = k
60 41 59 eqtr3d ⊢ φ ∧ i j ⊆ B ∧ k ∈ S ∧ i + G k = j → inv g ⁡ G ⁡ i + G j = k
61 simplr ⊢ φ ∧ i j ⊆ B ∧ k ∈ S ∧ i + G k = j → k ∈ S
62 60 61 eqeltrd ⊢ φ ∧ i j ⊆ B ∧ k ∈ S ∧ i + G k = j → inv g ⁡ G ⁡ i + G j ∈ S
63 62 r19.29an ⊢ φ ∧ i j ⊆ B ∧ ∃ k ∈ S i + G k = j → inv g ⁡ G ⁡ i + G j ∈ S
64 39 63 impbida ⊢ φ ∧ i j ⊆ B → inv g ⁡ G ⁡ i + G j ∈ S ↔ ∃ k ∈ S i + G k = j
65 64 pm5.32da ⊢ φ → i j ⊆ B ∧ inv g ⁡ G ⁡ i + G j ∈ S ↔ i j ⊆ B ∧ ∃ k ∈ S i + G k = j
66 65 opabbidv ⊢ φ → i j | i j ⊆ B ∧ inv g ⁡ G ⁡ i + G j ∈ S = i j | i j ⊆ B ∧ ∃ k ∈ S i + G k = j
67 13 66 eqtrd ⊢ φ → G ~ QG S = i j | i j ⊆ B ∧ ∃ k ∈ S i + G k = j
68 67 eceq2d ⊢ φ → X G ~ QG S = X i j | i j ⊆ B ∧ ∃ k ∈ S i + G k = j
69 eqid ⊢ i j | i j ⊆ B ∧ ∃ k ∈ S i + G k = j = i j | i j ⊆ B ∧ ∃ k ∈ S i + G k = j
70 6 grpmndd ⊢ φ → G ∈ Mnd
71 1 10 2 69 70 8 4 lsmsnorb2 ⊢ φ → X ⊕ ˙ S = X i j | i j ⊆ B ∧ ∃ k ∈ S i + G k = j
72 68 71 eqtr4d ⊢ φ → X G ~ QG S = X ⊕ ˙ S