Proof of Theorem gastacos
Step | Hyp | Ref
| Expression |
1 | | gasta.1 |
. . . . . . 7
⊢ 𝑋 = (Base‘𝐺) |
2 | | gasta.2 |
. . . . . . 7
⊢ 𝐻 = {𝑢 ∈ 𝑋 ∣ (𝑢 ⊕ 𝐴) = 𝐴} |
3 | 1, 2 | gastacl 18830 |
. . . . . 6
⊢ (( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) → 𝐻 ∈ (SubGrp‘𝐺)) |
4 | 3 | adantr 480 |
. . . . 5
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → 𝐻 ∈ (SubGrp‘𝐺)) |
5 | | subgrcl 18675 |
. . . . 5
⊢ (𝐻 ∈ (SubGrp‘𝐺) → 𝐺 ∈ Grp) |
6 | 4, 5 | syl 17 |
. . . 4
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → 𝐺 ∈ Grp) |
7 | 1 | subgss 18671 |
. . . . 5
⊢ (𝐻 ∈ (SubGrp‘𝐺) → 𝐻 ⊆ 𝑋) |
8 | 4, 7 | syl 17 |
. . . 4
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → 𝐻 ⊆ 𝑋) |
9 | | eqid 2738 |
. . . . 5
⊢
(invg‘𝐺) = (invg‘𝐺) |
10 | | eqid 2738 |
. . . . 5
⊢
(+g‘𝐺) = (+g‘𝐺) |
11 | | orbsta.r |
. . . . 5
⊢ ∼ =
(𝐺 ~QG
𝐻) |
12 | 1, 9, 10, 11 | eqgval 18720 |
. . . 4
⊢ ((𝐺 ∈ Grp ∧ 𝐻 ⊆ 𝑋) → (𝐵 ∼ 𝐶 ↔ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋 ∧ (((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝐻))) |
13 | 6, 8, 12 | syl2anc 583 |
. . 3
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → (𝐵 ∼ 𝐶 ↔ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋 ∧ (((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝐻))) |
14 | | df-3an 1087 |
. . 3
⊢ ((𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋 ∧ (((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝐻) ↔ ((𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋) ∧ (((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝐻)) |
15 | 13, 14 | bitrdi 286 |
. 2
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → (𝐵 ∼ 𝐶 ↔ ((𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋) ∧ (((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝐻))) |
16 | | simpr 484 |
. . 3
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) |
17 | 16 | biantrurd 532 |
. 2
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝐻 ↔ ((𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋) ∧ (((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝐻))) |
18 | | simpll 763 |
. . . . 5
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ⊕ ∈ (𝐺 GrpAct 𝑌)) |
19 | | simprl 767 |
. . . . . 6
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → 𝐵 ∈ 𝑋) |
20 | 1, 9 | grpinvcl 18542 |
. . . . . 6
⊢ ((𝐺 ∈ Grp ∧ 𝐵 ∈ 𝑋) → ((invg‘𝐺)‘𝐵) ∈ 𝑋) |
21 | 6, 19, 20 | syl2anc 583 |
. . . . 5
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ((invg‘𝐺)‘𝐵) ∈ 𝑋) |
22 | | simprr 769 |
. . . . 5
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → 𝐶 ∈ 𝑋) |
23 | | simplr 765 |
. . . . 5
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → 𝐴 ∈ 𝑌) |
24 | 1, 10 | gaass 18818 |
. . . . 5
⊢ (( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ (((invg‘𝐺)‘𝐵) ∈ 𝑋 ∧ 𝐶 ∈ 𝑋 ∧ 𝐴 ∈ 𝑌)) → ((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ⊕ 𝐴) = (((invg‘𝐺)‘𝐵) ⊕ (𝐶 ⊕ 𝐴))) |
25 | 18, 21, 22, 23, 24 | syl13anc 1370 |
. . . 4
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ⊕ 𝐴) = (((invg‘𝐺)‘𝐵) ⊕ (𝐶 ⊕ 𝐴))) |
26 | 25 | eqeq1d 2740 |
. . 3
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → (((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ⊕ 𝐴) = 𝐴 ↔ (((invg‘𝐺)‘𝐵) ⊕ (𝐶 ⊕ 𝐴)) = 𝐴)) |
27 | 1, 10 | grpcl 18500 |
. . . . 5
⊢ ((𝐺 ∈ Grp ∧
((invg‘𝐺)‘𝐵) ∈ 𝑋 ∧ 𝐶 ∈ 𝑋) → (((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝑋) |
28 | 6, 21, 22, 27 | syl3anc 1369 |
. . . 4
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → (((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝑋) |
29 | | oveq1 7262 |
. . . . . . 7
⊢ (𝑢 =
(((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) → (𝑢 ⊕ 𝐴) = ((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ⊕ 𝐴)) |
30 | 29 | eqeq1d 2740 |
. . . . . 6
⊢ (𝑢 =
(((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) → ((𝑢 ⊕ 𝐴) = 𝐴 ↔ ((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ⊕ 𝐴) = 𝐴)) |
31 | 30, 2 | elrab2 3620 |
. . . . 5
⊢
((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝐻 ↔ ((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝑋 ∧ ((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ⊕ 𝐴) = 𝐴)) |
32 | 31 | baib 535 |
. . . 4
⊢
((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝑋 → ((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝐻 ↔ ((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ⊕ 𝐴) = 𝐴)) |
33 | 28, 32 | syl 17 |
. . 3
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝐻 ↔ ((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ⊕ 𝐴) = 𝐴)) |
34 | 1 | gaf 18816 |
. . . . . 6
⊢ ( ⊕ ∈
(𝐺 GrpAct 𝑌) → ⊕ :(𝑋 × 𝑌)⟶𝑌) |
35 | 18, 34 | syl 17 |
. . . . 5
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ⊕ :(𝑋 × 𝑌)⟶𝑌) |
36 | 35, 22, 23 | fovrnd 7422 |
. . . 4
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → (𝐶 ⊕ 𝐴) ∈ 𝑌) |
37 | 1, 9 | gacan 18826 |
. . . 4
⊢ (( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐴 ∈ 𝑌 ∧ (𝐶 ⊕ 𝐴) ∈ 𝑌)) → ((𝐵 ⊕ 𝐴) = (𝐶 ⊕ 𝐴) ↔ (((invg‘𝐺)‘𝐵) ⊕ (𝐶 ⊕ 𝐴)) = 𝐴)) |
38 | 18, 19, 23, 36, 37 | syl13anc 1370 |
. . 3
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ((𝐵 ⊕ 𝐴) = (𝐶 ⊕ 𝐴) ↔ (((invg‘𝐺)‘𝐵) ⊕ (𝐶 ⊕ 𝐴)) = 𝐴)) |
39 | 26, 33, 38 | 3bitr4d 310 |
. 2
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ((((invg‘𝐺)‘𝐵)(+g‘𝐺)𝐶) ∈ 𝐻 ↔ (𝐵 ⊕ 𝐴) = (𝐶 ⊕ 𝐴))) |
40 | 15, 17, 39 | 3bitr2d 306 |
1
⊢ ((( ⊕ ∈
(𝐺 GrpAct 𝑌) ∧ 𝐴 ∈ 𝑌) ∧ (𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → (𝐵 ∼ 𝐶 ↔ (𝐵 ⊕ 𝐴) = (𝐶 ⊕ 𝐴))) |