Proof of Theorem subgmulg
| Step | Hyp | Ref
| Expression |
| 1 | | subgmulg.h |
. . . . . 6
⊢ 𝐻 = (𝐺 ↾s 𝑆) |
| 2 | | eqid 2196 |
. . . . . 6
⊢
(0g‘𝐺) = (0g‘𝐺) |
| 3 | 1, 2 | subg0 13386 |
. . . . 5
⊢ (𝑆 ∈ (SubGrp‘𝐺) →
(0g‘𝐺) =
(0g‘𝐻)) |
| 4 | 3 | 3ad2ant1 1020 |
. . . 4
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → (0g‘𝐺) = (0g‘𝐻)) |
| 5 | 4 | ifeq1d 3579 |
. . 3
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → if(𝑁 = 0, (0g‘𝐺), if(0 < 𝑁, (seq1((+g‘𝐺), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁)))) = if(𝑁 = 0, (0g‘𝐻), if(0 < 𝑁, (seq1((+g‘𝐺), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁))))) |
| 6 | 1 | a1i 9 |
. . . . . . . . . . 11
⊢ (𝑆 ∈ (SubGrp‘𝐺) → 𝐻 = (𝐺 ↾s 𝑆)) |
| 7 | | eqid 2196 |
. . . . . . . . . . . 12
⊢
(+g‘𝐺) = (+g‘𝐺) |
| 8 | 7 | a1i 9 |
. . . . . . . . . . 11
⊢ (𝑆 ∈ (SubGrp‘𝐺) →
(+g‘𝐺) =
(+g‘𝐺)) |
| 9 | | id 19 |
. . . . . . . . . . 11
⊢ (𝑆 ∈ (SubGrp‘𝐺) → 𝑆 ∈ (SubGrp‘𝐺)) |
| 10 | | subgrcl 13385 |
. . . . . . . . . . 11
⊢ (𝑆 ∈ (SubGrp‘𝐺) → 𝐺 ∈ Grp) |
| 11 | 6, 8, 9, 10 | ressplusgd 12831 |
. . . . . . . . . 10
⊢ (𝑆 ∈ (SubGrp‘𝐺) →
(+g‘𝐺) =
(+g‘𝐻)) |
| 12 | 11 | 3ad2ant1 1020 |
. . . . . . . . 9
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → (+g‘𝐺) = (+g‘𝐻)) |
| 13 | 12 | seqeq2d 10563 |
. . . . . . . 8
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → seq1((+g‘𝐺), (ℕ × {𝑋})) =
seq1((+g‘𝐻), (ℕ × {𝑋}))) |
| 14 | 13 | adantr 276 |
. . . . . . 7
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ ¬ 𝑁 = 0) → seq1((+g‘𝐺), (ℕ × {𝑋})) =
seq1((+g‘𝐻), (ℕ × {𝑋}))) |
| 15 | 14 | fveq1d 5563 |
. . . . . 6
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ ¬ 𝑁 = 0) →
(seq1((+g‘𝐺), (ℕ × {𝑋}))‘𝑁) = (seq1((+g‘𝐻), (ℕ × {𝑋}))‘𝑁)) |
| 16 | 15 | ifeq1d 3579 |
. . . . 5
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ ¬ 𝑁 = 0) → if(0 < 𝑁, (seq1((+g‘𝐺), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁))) = if(0 < 𝑁, (seq1((+g‘𝐻), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁)))) |
| 17 | | simprl 529 |
. . . . . . . . . 10
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ (¬ 𝑁 = 0 ∧ ¬ 0 < 𝑁)) → ¬ 𝑁 = 0) |
| 18 | | simprr 531 |
. . . . . . . . . 10
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ (¬ 𝑁 = 0 ∧ ¬ 0 < 𝑁)) → ¬ 0 < 𝑁) |
| 19 | | simp2 1000 |
. . . . . . . . . . . 12
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → 𝑁 ∈ ℤ) |
| 20 | | ztri3or0 9385 |
. . . . . . . . . . . 12
⊢ (𝑁 ∈ ℤ → (𝑁 < 0 ∨ 𝑁 = 0 ∨ 0 < 𝑁)) |
| 21 | 19, 20 | syl 14 |
. . . . . . . . . . 11
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → (𝑁 < 0 ∨ 𝑁 = 0 ∨ 0 < 𝑁)) |
| 22 | 21 | adantr 276 |
. . . . . . . . . 10
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ (¬ 𝑁 = 0 ∧ ¬ 0 < 𝑁)) → (𝑁 < 0 ∨ 𝑁 = 0 ∨ 0 < 𝑁)) |
| 23 | 17, 18, 22 | ecase23d 1361 |
. . . . . . . . 9
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ (¬ 𝑁 = 0 ∧ ¬ 0 < 𝑁)) → 𝑁 < 0) |
| 24 | | simpl1 1002 |
. . . . . . . . . 10
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ 𝑁 < 0) → 𝑆 ∈ (SubGrp‘𝐺)) |
| 25 | 19 | adantr 276 |
. . . . . . . . . . . . . 14
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ 𝑁 < 0) → 𝑁 ∈ ℤ) |
| 26 | 25 | znegcld 9467 |
. . . . . . . . . . . . 13
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ 𝑁 < 0) → -𝑁 ∈ ℤ) |
| 27 | 19 | zred 9465 |
. . . . . . . . . . . . . . 15
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → 𝑁 ∈ ℝ) |
| 28 | 27 | lt0neg1d 8559 |
. . . . . . . . . . . . . 14
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → (𝑁 < 0 ↔ 0 < -𝑁)) |
| 29 | 28 | biimpa 296 |
. . . . . . . . . . . . 13
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ 𝑁 < 0) → 0 < -𝑁) |
| 30 | | elnnz 9353 |
. . . . . . . . . . . . 13
⊢ (-𝑁 ∈ ℕ ↔ (-𝑁 ∈ ℤ ∧ 0 <
-𝑁)) |
| 31 | 26, 29, 30 | sylanbrc 417 |
. . . . . . . . . . . 12
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ 𝑁 < 0) → -𝑁 ∈ ℕ) |
| 32 | | eqid 2196 |
. . . . . . . . . . . . . . . 16
⊢
(Base‘𝐺) =
(Base‘𝐺) |
| 33 | 32 | subgss 13380 |
. . . . . . . . . . . . . . 15
⊢ (𝑆 ∈ (SubGrp‘𝐺) → 𝑆 ⊆ (Base‘𝐺)) |
| 34 | 33 | 3ad2ant1 1020 |
. . . . . . . . . . . . . 14
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → 𝑆 ⊆ (Base‘𝐺)) |
| 35 | | simp3 1001 |
. . . . . . . . . . . . . 14
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → 𝑋 ∈ 𝑆) |
| 36 | 34, 35 | sseldd 3185 |
. . . . . . . . . . . . 13
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → 𝑋 ∈ (Base‘𝐺)) |
| 37 | 36 | adantr 276 |
. . . . . . . . . . . 12
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ 𝑁 < 0) → 𝑋 ∈ (Base‘𝐺)) |
| 38 | | subgmulgcl.t |
. . . . . . . . . . . . 13
⊢ · =
(.g‘𝐺) |
| 39 | | eqid 2196 |
. . . . . . . . . . . . 13
⊢
seq1((+g‘𝐺), (ℕ × {𝑋})) = seq1((+g‘𝐺), (ℕ × {𝑋})) |
| 40 | 32, 7, 38, 39 | mulgnn 13332 |
. . . . . . . . . . . 12
⊢ ((-𝑁 ∈ ℕ ∧ 𝑋 ∈ (Base‘𝐺)) → (-𝑁 · 𝑋) = (seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁)) |
| 41 | 31, 37, 40 | syl2anc 411 |
. . . . . . . . . . 11
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ 𝑁 < 0) → (-𝑁 · 𝑋) = (seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁)) |
| 42 | 35 | adantr 276 |
. . . . . . . . . . . 12
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ 𝑁 < 0) → 𝑋 ∈ 𝑆) |
| 43 | 38 | subgmulgcl 13393 |
. . . . . . . . . . . 12
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ -𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → (-𝑁 · 𝑋) ∈ 𝑆) |
| 44 | 24, 26, 42, 43 | syl3anc 1249 |
. . . . . . . . . . 11
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ 𝑁 < 0) → (-𝑁 · 𝑋) ∈ 𝑆) |
| 45 | 41, 44 | eqeltrrd 2274 |
. . . . . . . . . 10
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ 𝑁 < 0) →
(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁) ∈ 𝑆) |
| 46 | | eqid 2196 |
. . . . . . . . . . 11
⊢
(invg‘𝐺) = (invg‘𝐺) |
| 47 | | eqid 2196 |
. . . . . . . . . . 11
⊢
(invg‘𝐻) = (invg‘𝐻) |
| 48 | 1, 46, 47 | subginv 13387 |
. . . . . . . . . 10
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧
(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁) ∈ 𝑆) → ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁)) = ((invg‘𝐻)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁))) |
| 49 | 24, 45, 48 | syl2anc 411 |
. . . . . . . . 9
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ 𝑁 < 0) →
((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁)) = ((invg‘𝐻)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁))) |
| 50 | 23, 49 | syldan 282 |
. . . . . . . 8
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ (¬ 𝑁 = 0 ∧ ¬ 0 < 𝑁)) → ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁)) = ((invg‘𝐻)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁))) |
| 51 | 13 | adantr 276 |
. . . . . . . . . 10
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ (¬ 𝑁 = 0 ∧ ¬ 0 < 𝑁)) → seq1((+g‘𝐺), (ℕ × {𝑋})) =
seq1((+g‘𝐻), (ℕ × {𝑋}))) |
| 52 | 51 | fveq1d 5563 |
. . . . . . . . 9
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ (¬ 𝑁 = 0 ∧ ¬ 0 < 𝑁)) → (seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁) = (seq1((+g‘𝐻), (ℕ × {𝑋}))‘-𝑁)) |
| 53 | 52 | fveq2d 5565 |
. . . . . . . 8
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ (¬ 𝑁 = 0 ∧ ¬ 0 < 𝑁)) → ((invg‘𝐻)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁)) = ((invg‘𝐻)‘(seq1((+g‘𝐻), (ℕ × {𝑋}))‘-𝑁))) |
| 54 | 50, 53 | eqtrd 2229 |
. . . . . . 7
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ (¬ 𝑁 = 0 ∧ ¬ 0 < 𝑁)) → ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁)) = ((invg‘𝐻)‘(seq1((+g‘𝐻), (ℕ × {𝑋}))‘-𝑁))) |
| 55 | 54 | anassrs 400 |
. . . . . 6
⊢ ((((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁)) = ((invg‘𝐻)‘(seq1((+g‘𝐻), (ℕ × {𝑋}))‘-𝑁))) |
| 56 | | 0z 9354 |
. . . . . . 7
⊢ 0 ∈
ℤ |
| 57 | 19 | adantr 276 |
. . . . . . 7
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ ¬ 𝑁 = 0) → 𝑁 ∈ ℤ) |
| 58 | | zdclt 9420 |
. . . . . . 7
⊢ ((0
∈ ℤ ∧ 𝑁
∈ ℤ) → DECID 0 < 𝑁) |
| 59 | 56, 57, 58 | sylancr 414 |
. . . . . 6
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ ¬ 𝑁 = 0) → DECID 0 <
𝑁) |
| 60 | 55, 59 | ifeq2dadc 3593 |
. . . . 5
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ ¬ 𝑁 = 0) → if(0 < 𝑁, (seq1((+g‘𝐻), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁))) = if(0 < 𝑁, (seq1((+g‘𝐻), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐻)‘(seq1((+g‘𝐻), (ℕ × {𝑋}))‘-𝑁)))) |
| 61 | 16, 60 | eqtrd 2229 |
. . . 4
⊢ (((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) ∧ ¬ 𝑁 = 0) → if(0 < 𝑁, (seq1((+g‘𝐺), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁))) = if(0 < 𝑁, (seq1((+g‘𝐻), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐻)‘(seq1((+g‘𝐻), (ℕ × {𝑋}))‘-𝑁)))) |
| 62 | | 0zd 9355 |
. . . . 5
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → 0 ∈ ℤ) |
| 63 | | zdceq 9418 |
. . . . 5
⊢ ((𝑁 ∈ ℤ ∧ 0 ∈
ℤ) → DECID 𝑁 = 0) |
| 64 | 19, 62, 63 | syl2anc 411 |
. . . 4
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → DECID 𝑁 = 0) |
| 65 | 61, 64 | ifeq2dadc 3593 |
. . 3
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → if(𝑁 = 0, (0g‘𝐻), if(0 < 𝑁, (seq1((+g‘𝐺), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁)))) = if(𝑁 = 0, (0g‘𝐻), if(0 < 𝑁, (seq1((+g‘𝐻), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐻)‘(seq1((+g‘𝐻), (ℕ × {𝑋}))‘-𝑁))))) |
| 66 | 5, 65 | eqtrd 2229 |
. 2
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → if(𝑁 = 0, (0g‘𝐺), if(0 < 𝑁, (seq1((+g‘𝐺), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁)))) = if(𝑁 = 0, (0g‘𝐻), if(0 < 𝑁, (seq1((+g‘𝐻), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐻)‘(seq1((+g‘𝐻), (ℕ × {𝑋}))‘-𝑁))))) |
| 67 | 32, 7, 2, 46, 38, 39 | mulgval 13328 |
. . 3
⊢ ((𝑁 ∈ ℤ ∧ 𝑋 ∈ (Base‘𝐺)) → (𝑁 · 𝑋) = if(𝑁 = 0, (0g‘𝐺), if(0 < 𝑁, (seq1((+g‘𝐺), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁))))) |
| 68 | 19, 36, 67 | syl2anc 411 |
. 2
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → (𝑁 · 𝑋) = if(𝑁 = 0, (0g‘𝐺), if(0 < 𝑁, (seq1((+g‘𝐺), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐺)‘(seq1((+g‘𝐺), (ℕ × {𝑋}))‘-𝑁))))) |
| 69 | 1 | subgbas 13384 |
. . . . 5
⊢ (𝑆 ∈ (SubGrp‘𝐺) → 𝑆 = (Base‘𝐻)) |
| 70 | 69 | 3ad2ant1 1020 |
. . . 4
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → 𝑆 = (Base‘𝐻)) |
| 71 | 35, 70 | eleqtrd 2275 |
. . 3
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → 𝑋 ∈ (Base‘𝐻)) |
| 72 | | eqid 2196 |
. . . 4
⊢
(Base‘𝐻) =
(Base‘𝐻) |
| 73 | | eqid 2196 |
. . . 4
⊢
(+g‘𝐻) = (+g‘𝐻) |
| 74 | | eqid 2196 |
. . . 4
⊢
(0g‘𝐻) = (0g‘𝐻) |
| 75 | | subgmulg.t |
. . . 4
⊢ ∙ =
(.g‘𝐻) |
| 76 | | eqid 2196 |
. . . 4
⊢
seq1((+g‘𝐻), (ℕ × {𝑋})) = seq1((+g‘𝐻), (ℕ × {𝑋})) |
| 77 | 72, 73, 74, 47, 75, 76 | mulgval 13328 |
. . 3
⊢ ((𝑁 ∈ ℤ ∧ 𝑋 ∈ (Base‘𝐻)) → (𝑁 ∙ 𝑋) = if(𝑁 = 0, (0g‘𝐻), if(0 < 𝑁, (seq1((+g‘𝐻), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐻)‘(seq1((+g‘𝐻), (ℕ × {𝑋}))‘-𝑁))))) |
| 78 | 19, 71, 77 | syl2anc 411 |
. 2
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → (𝑁 ∙ 𝑋) = if(𝑁 = 0, (0g‘𝐻), if(0 < 𝑁, (seq1((+g‘𝐻), (ℕ × {𝑋}))‘𝑁), ((invg‘𝐻)‘(seq1((+g‘𝐻), (ℕ × {𝑋}))‘-𝑁))))) |
| 79 | 66, 68, 78 | 3eqtr4d 2239 |
1
⊢ ((𝑆 ∈ (SubGrp‘𝐺) ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝑆) → (𝑁 · 𝑋) = (𝑁 ∙ 𝑋)) |