| Step | Hyp | Ref
 | Expression | 
| 1 |   | intssunim 3896 | 
. . . 4
⊢
(∃𝑤 𝑤 ∈ 𝑆 → ∩ 𝑆 ⊆ ∪ 𝑆) | 
| 2 | 1 | adantl 277 | 
. . 3
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → ∩ 𝑆 ⊆ ∪ 𝑆) | 
| 3 |   | ssel2 3178 | 
. . . . . . 7
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ 𝑔 ∈ 𝑆) → 𝑔 ∈ (SubGrp‘𝐺)) | 
| 4 | 3 | adantlr 477 | 
. . . . . 6
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑔 ∈ 𝑆) → 𝑔 ∈ (SubGrp‘𝐺)) | 
| 5 |   | eqid 2196 | 
. . . . . . 7
⊢
(Base‘𝐺) =
(Base‘𝐺) | 
| 6 | 5 | subgss 13304 | 
. . . . . 6
⊢ (𝑔 ∈ (SubGrp‘𝐺) → 𝑔 ⊆ (Base‘𝐺)) | 
| 7 | 4, 6 | syl 14 | 
. . . . 5
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑔 ∈ 𝑆) → 𝑔 ⊆ (Base‘𝐺)) | 
| 8 | 7 | ralrimiva 2570 | 
. . . 4
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → ∀𝑔 ∈ 𝑆 𝑔 ⊆ (Base‘𝐺)) | 
| 9 |   | unissb 3869 | 
. . . 4
⊢ (∪ 𝑆
⊆ (Base‘𝐺)
↔ ∀𝑔 ∈
𝑆 𝑔 ⊆ (Base‘𝐺)) | 
| 10 | 8, 9 | sylibr 134 | 
. . 3
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → ∪ 𝑆 ⊆ (Base‘𝐺)) | 
| 11 | 2, 10 | sstrd 3193 | 
. 2
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → ∩ 𝑆 ⊆ (Base‘𝐺)) | 
| 12 |   | eqid 2196 | 
. . . . . . 7
⊢
(0g‘𝐺) = (0g‘𝐺) | 
| 13 | 12 | subg0cl 13312 | 
. . . . . 6
⊢ (𝑔 ∈ (SubGrp‘𝐺) →
(0g‘𝐺)
∈ 𝑔) | 
| 14 | 4, 13 | syl 14 | 
. . . . 5
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑔 ∈ 𝑆) → (0g‘𝐺) ∈ 𝑔) | 
| 15 | 14 | ralrimiva 2570 | 
. . . 4
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → ∀𝑔 ∈ 𝑆 (0g‘𝐺) ∈ 𝑔) | 
| 16 |   | ssel 3177 | 
. . . . . . . 8
⊢ (𝑆 ⊆ (SubGrp‘𝐺) → (𝑤 ∈ 𝑆 → 𝑤 ∈ (SubGrp‘𝐺))) | 
| 17 | 16 | eximdv 1894 | 
. . . . . . 7
⊢ (𝑆 ⊆ (SubGrp‘𝐺) → (∃𝑤 𝑤 ∈ 𝑆 → ∃𝑤 𝑤 ∈ (SubGrp‘𝐺))) | 
| 18 | 17 | imp 124 | 
. . . . . 6
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → ∃𝑤 𝑤 ∈ (SubGrp‘𝐺)) | 
| 19 |   | subgrcl 13309 | 
. . . . . . 7
⊢ (𝑤 ∈ (SubGrp‘𝐺) → 𝐺 ∈ Grp) | 
| 20 | 19 | exlimiv 1612 | 
. . . . . 6
⊢
(∃𝑤 𝑤 ∈ (SubGrp‘𝐺) → 𝐺 ∈ Grp) | 
| 21 | 18, 20 | syl 14 | 
. . . . 5
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → 𝐺 ∈ Grp) | 
| 22 | 5, 12 | grpidcl 13161 | 
. . . . 5
⊢ (𝐺 ∈ Grp →
(0g‘𝐺)
∈ (Base‘𝐺)) | 
| 23 |   | elintg 3882 | 
. . . . 5
⊢
((0g‘𝐺) ∈ (Base‘𝐺) → ((0g‘𝐺) ∈ ∩ 𝑆
↔ ∀𝑔 ∈
𝑆
(0g‘𝐺)
∈ 𝑔)) | 
| 24 | 21, 22, 23 | 3syl 17 | 
. . . 4
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → ((0g‘𝐺) ∈ ∩ 𝑆
↔ ∀𝑔 ∈
𝑆
(0g‘𝐺)
∈ 𝑔)) | 
| 25 | 15, 24 | mpbird 167 | 
. . 3
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → (0g‘𝐺) ∈ ∩ 𝑆) | 
| 26 |   | elex2 2779 | 
. . 3
⊢
((0g‘𝐺) ∈ ∩ 𝑆 → ∃𝑤 𝑤 ∈ ∩ 𝑆) | 
| 27 | 25, 26 | syl 14 | 
. 2
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → ∃𝑤 𝑤 ∈ ∩ 𝑆) | 
| 28 | 4 | adantlr 477 | 
. . . . . . . . 9
⊢ ((((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ (𝑥 ∈ ∩ 𝑆 ∧ 𝑦 ∈ ∩ 𝑆)) ∧ 𝑔 ∈ 𝑆) → 𝑔 ∈ (SubGrp‘𝐺)) | 
| 29 |   | simprl 529 | 
. . . . . . . . . 10
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ (𝑥 ∈ ∩ 𝑆 ∧ 𝑦 ∈ ∩ 𝑆)) → 𝑥 ∈ ∩ 𝑆) | 
| 30 |   | elinti 3883 | 
. . . . . . . . . . 11
⊢ (𝑥 ∈ ∩ 𝑆
→ (𝑔 ∈ 𝑆 → 𝑥 ∈ 𝑔)) | 
| 31 | 30 | imp 124 | 
. . . . . . . . . 10
⊢ ((𝑥 ∈ ∩ 𝑆
∧ 𝑔 ∈ 𝑆) → 𝑥 ∈ 𝑔) | 
| 32 | 29, 31 | sylan 283 | 
. . . . . . . . 9
⊢ ((((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ (𝑥 ∈ ∩ 𝑆 ∧ 𝑦 ∈ ∩ 𝑆)) ∧ 𝑔 ∈ 𝑆) → 𝑥 ∈ 𝑔) | 
| 33 |   | simprr 531 | 
. . . . . . . . . 10
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ (𝑥 ∈ ∩ 𝑆 ∧ 𝑦 ∈ ∩ 𝑆)) → 𝑦 ∈ ∩ 𝑆) | 
| 34 |   | elinti 3883 | 
. . . . . . . . . . 11
⊢ (𝑦 ∈ ∩ 𝑆
→ (𝑔 ∈ 𝑆 → 𝑦 ∈ 𝑔)) | 
| 35 | 34 | imp 124 | 
. . . . . . . . . 10
⊢ ((𝑦 ∈ ∩ 𝑆
∧ 𝑔 ∈ 𝑆) → 𝑦 ∈ 𝑔) | 
| 36 | 33, 35 | sylan 283 | 
. . . . . . . . 9
⊢ ((((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ (𝑥 ∈ ∩ 𝑆 ∧ 𝑦 ∈ ∩ 𝑆)) ∧ 𝑔 ∈ 𝑆) → 𝑦 ∈ 𝑔) | 
| 37 |   | eqid 2196 | 
. . . . . . . . . 10
⊢
(+g‘𝐺) = (+g‘𝐺) | 
| 38 | 37 | subgcl 13314 | 
. . . . . . . . 9
⊢ ((𝑔 ∈ (SubGrp‘𝐺) ∧ 𝑥 ∈ 𝑔 ∧ 𝑦 ∈ 𝑔) → (𝑥(+g‘𝐺)𝑦) ∈ 𝑔) | 
| 39 | 28, 32, 36, 38 | syl3anc 1249 | 
. . . . . . . 8
⊢ ((((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ (𝑥 ∈ ∩ 𝑆 ∧ 𝑦 ∈ ∩ 𝑆)) ∧ 𝑔 ∈ 𝑆) → (𝑥(+g‘𝐺)𝑦) ∈ 𝑔) | 
| 40 | 39 | ralrimiva 2570 | 
. . . . . . 7
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ (𝑥 ∈ ∩ 𝑆 ∧ 𝑦 ∈ ∩ 𝑆)) → ∀𝑔 ∈ 𝑆 (𝑥(+g‘𝐺)𝑦) ∈ 𝑔) | 
| 41 |   | vex 2766 | 
. . . . . . . . . . 11
⊢ 𝑥 ∈ V | 
| 42 | 41 | a1i 9 | 
. . . . . . . . . 10
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → 𝑥 ∈ V) | 
| 43 |   | plusgslid 12790 | 
. . . . . . . . . . . 12
⊢
(+g = Slot (+g‘ndx) ∧
(+g‘ndx) ∈ ℕ) | 
| 44 | 43 | slotex 12705 | 
. . . . . . . . . . 11
⊢ (𝐺 ∈ Grp →
(+g‘𝐺)
∈ V) | 
| 45 | 18, 20, 44 | 3syl 17 | 
. . . . . . . . . 10
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → (+g‘𝐺) ∈ V) | 
| 46 |   | vex 2766 | 
. . . . . . . . . . 11
⊢ 𝑦 ∈ V | 
| 47 | 46 | a1i 9 | 
. . . . . . . . . 10
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → 𝑦 ∈ V) | 
| 48 |   | ovexg 5956 | 
. . . . . . . . . 10
⊢ ((𝑥 ∈ V ∧
(+g‘𝐺)
∈ V ∧ 𝑦 ∈ V)
→ (𝑥(+g‘𝐺)𝑦) ∈ V) | 
| 49 | 42, 45, 47, 48 | syl3anc 1249 | 
. . . . . . . . 9
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → (𝑥(+g‘𝐺)𝑦) ∈ V) | 
| 50 |   | elintg 3882 | 
. . . . . . . . 9
⊢ ((𝑥(+g‘𝐺)𝑦) ∈ V → ((𝑥(+g‘𝐺)𝑦) ∈ ∩ 𝑆 ↔ ∀𝑔 ∈ 𝑆 (𝑥(+g‘𝐺)𝑦) ∈ 𝑔)) | 
| 51 | 49, 50 | syl 14 | 
. . . . . . . 8
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → ((𝑥(+g‘𝐺)𝑦) ∈ ∩ 𝑆 ↔ ∀𝑔 ∈ 𝑆 (𝑥(+g‘𝐺)𝑦) ∈ 𝑔)) | 
| 52 | 51 | adantr 276 | 
. . . . . . 7
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ (𝑥 ∈ ∩ 𝑆 ∧ 𝑦 ∈ ∩ 𝑆)) → ((𝑥(+g‘𝐺)𝑦) ∈ ∩ 𝑆 ↔ ∀𝑔 ∈ 𝑆 (𝑥(+g‘𝐺)𝑦) ∈ 𝑔)) | 
| 53 | 40, 52 | mpbird 167 | 
. . . . . 6
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ (𝑥 ∈ ∩ 𝑆 ∧ 𝑦 ∈ ∩ 𝑆)) → (𝑥(+g‘𝐺)𝑦) ∈ ∩ 𝑆) | 
| 54 | 53 | anassrs 400 | 
. . . . 5
⊢ ((((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑥 ∈ ∩ 𝑆) ∧ 𝑦 ∈ ∩ 𝑆) → (𝑥(+g‘𝐺)𝑦) ∈ ∩ 𝑆) | 
| 55 | 54 | ralrimiva 2570 | 
. . . 4
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑥 ∈ ∩ 𝑆) → ∀𝑦 ∈ ∩ 𝑆(𝑥(+g‘𝐺)𝑦) ∈ ∩ 𝑆) | 
| 56 | 4 | adantlr 477 | 
. . . . . . 7
⊢ ((((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑥 ∈ ∩ 𝑆) ∧ 𝑔 ∈ 𝑆) → 𝑔 ∈ (SubGrp‘𝐺)) | 
| 57 | 31 | adantll 476 | 
. . . . . . 7
⊢ ((((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑥 ∈ ∩ 𝑆) ∧ 𝑔 ∈ 𝑆) → 𝑥 ∈ 𝑔) | 
| 58 |   | eqid 2196 | 
. . . . . . . 8
⊢
(invg‘𝐺) = (invg‘𝐺) | 
| 59 | 58 | subginvcl 13313 | 
. . . . . . 7
⊢ ((𝑔 ∈ (SubGrp‘𝐺) ∧ 𝑥 ∈ 𝑔) → ((invg‘𝐺)‘𝑥) ∈ 𝑔) | 
| 60 | 56, 57, 59 | syl2anc 411 | 
. . . . . 6
⊢ ((((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑥 ∈ ∩ 𝑆) ∧ 𝑔 ∈ 𝑆) → ((invg‘𝐺)‘𝑥) ∈ 𝑔) | 
| 61 | 60 | ralrimiva 2570 | 
. . . . 5
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑥 ∈ ∩ 𝑆) → ∀𝑔 ∈ 𝑆 ((invg‘𝐺)‘𝑥) ∈ 𝑔) | 
| 62 | 21 | adantr 276 | 
. . . . . . 7
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑥 ∈ ∩ 𝑆) → 𝐺 ∈ Grp) | 
| 63 | 11 | sselda 3183 | 
. . . . . . 7
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑥 ∈ ∩ 𝑆) → 𝑥 ∈ (Base‘𝐺)) | 
| 64 | 5, 58 | grpinvcl 13180 | 
. . . . . . 7
⊢ ((𝐺 ∈ Grp ∧ 𝑥 ∈ (Base‘𝐺)) →
((invg‘𝐺)‘𝑥) ∈ (Base‘𝐺)) | 
| 65 | 62, 63, 64 | syl2anc 411 | 
. . . . . 6
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑥 ∈ ∩ 𝑆) →
((invg‘𝐺)‘𝑥) ∈ (Base‘𝐺)) | 
| 66 |   | elintg 3882 | 
. . . . . 6
⊢
(((invg‘𝐺)‘𝑥) ∈ (Base‘𝐺) → (((invg‘𝐺)‘𝑥) ∈ ∩ 𝑆 ↔ ∀𝑔 ∈ 𝑆 ((invg‘𝐺)‘𝑥) ∈ 𝑔)) | 
| 67 | 65, 66 | syl 14 | 
. . . . 5
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑥 ∈ ∩ 𝑆) →
(((invg‘𝐺)‘𝑥) ∈ ∩ 𝑆 ↔ ∀𝑔 ∈ 𝑆 ((invg‘𝐺)‘𝑥) ∈ 𝑔)) | 
| 68 | 61, 67 | mpbird 167 | 
. . . 4
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑥 ∈ ∩ 𝑆) →
((invg‘𝐺)‘𝑥) ∈ ∩ 𝑆) | 
| 69 | 55, 68 | jca 306 | 
. . 3
⊢ (((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) ∧ 𝑥 ∈ ∩ 𝑆) → (∀𝑦 ∈ ∩ 𝑆(𝑥(+g‘𝐺)𝑦) ∈ ∩ 𝑆 ∧
((invg‘𝐺)‘𝑥) ∈ ∩ 𝑆)) | 
| 70 | 69 | ralrimiva 2570 | 
. 2
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → ∀𝑥 ∈ ∩ 𝑆(∀𝑦 ∈ ∩ 𝑆(𝑥(+g‘𝐺)𝑦) ∈ ∩ 𝑆 ∧
((invg‘𝐺)‘𝑥) ∈ ∩ 𝑆)) | 
| 71 | 5, 37, 58 | issubg2m 13319 | 
. . 3
⊢ (𝐺 ∈ Grp → (∩ 𝑆
∈ (SubGrp‘𝐺)
↔ (∩ 𝑆 ⊆ (Base‘𝐺) ∧ ∃𝑤 𝑤 ∈ ∩ 𝑆 ∧ ∀𝑥 ∈ ∩ 𝑆(∀𝑦 ∈ ∩ 𝑆(𝑥(+g‘𝐺)𝑦) ∈ ∩ 𝑆 ∧
((invg‘𝐺)‘𝑥) ∈ ∩ 𝑆)))) | 
| 72 | 18, 20, 71 | 3syl 17 | 
. 2
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → (∩ 𝑆 ∈ (SubGrp‘𝐺) ↔ (∩ 𝑆
⊆ (Base‘𝐺)
∧ ∃𝑤 𝑤 ∈ ∩ 𝑆
∧ ∀𝑥 ∈
∩ 𝑆(∀𝑦 ∈ ∩ 𝑆(𝑥(+g‘𝐺)𝑦) ∈ ∩ 𝑆 ∧
((invg‘𝐺)‘𝑥) ∈ ∩ 𝑆)))) | 
| 73 | 11, 27, 70, 72 | mpbir3and 1182 | 
1
⊢ ((𝑆 ⊆ (SubGrp‘𝐺) ∧ ∃𝑤 𝑤 ∈ 𝑆) → ∩ 𝑆 ∈ (SubGrp‘𝐺)) |