| Step | Hyp | Ref
| Expression |
| 1 | | oveq1 6657 |
. . . . . 6
⊢ (𝑥 = 0 → (𝑥 · (𝐼‘𝑋)) = (0 · (𝐼‘𝑋))) |
| 2 | | oveq1 6657 |
. . . . . . 7
⊢ (𝑥 = 0 → (𝑥 · 𝑋) = (0 · 𝑋)) |
| 3 | 2 | fveq2d 6195 |
. . . . . 6
⊢ (𝑥 = 0 → (𝐼‘(𝑥 · 𝑋)) = (𝐼‘(0 · 𝑋))) |
| 4 | 1, 3 | eqeq12d 2637 |
. . . . 5
⊢ (𝑥 = 0 → ((𝑥 · (𝐼‘𝑋)) = (𝐼‘(𝑥 · 𝑋)) ↔ (0 · (𝐼‘𝑋)) = (𝐼‘(0 · 𝑋)))) |
| 5 | | oveq1 6657 |
. . . . . 6
⊢ (𝑥 = 𝑦 → (𝑥 · (𝐼‘𝑋)) = (𝑦 · (𝐼‘𝑋))) |
| 6 | | oveq1 6657 |
. . . . . . 7
⊢ (𝑥 = 𝑦 → (𝑥 · 𝑋) = (𝑦 · 𝑋)) |
| 7 | 6 | fveq2d 6195 |
. . . . . 6
⊢ (𝑥 = 𝑦 → (𝐼‘(𝑥 · 𝑋)) = (𝐼‘(𝑦 · 𝑋))) |
| 8 | 5, 7 | eqeq12d 2637 |
. . . . 5
⊢ (𝑥 = 𝑦 → ((𝑥 · (𝐼‘𝑋)) = (𝐼‘(𝑥 · 𝑋)) ↔ (𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋)))) |
| 9 | | oveq1 6657 |
. . . . . 6
⊢ (𝑥 = (𝑦 + 1) → (𝑥 · (𝐼‘𝑋)) = ((𝑦 + 1) · (𝐼‘𝑋))) |
| 10 | | oveq1 6657 |
. . . . . . 7
⊢ (𝑥 = (𝑦 + 1) → (𝑥 · 𝑋) = ((𝑦 + 1) · 𝑋)) |
| 11 | 10 | fveq2d 6195 |
. . . . . 6
⊢ (𝑥 = (𝑦 + 1) → (𝐼‘(𝑥 · 𝑋)) = (𝐼‘((𝑦 + 1) · 𝑋))) |
| 12 | 9, 11 | eqeq12d 2637 |
. . . . 5
⊢ (𝑥 = (𝑦 + 1) → ((𝑥 · (𝐼‘𝑋)) = (𝐼‘(𝑥 · 𝑋)) ↔ ((𝑦 + 1) · (𝐼‘𝑋)) = (𝐼‘((𝑦 + 1) · 𝑋)))) |
| 13 | | oveq1 6657 |
. . . . . 6
⊢ (𝑥 = -𝑦 → (𝑥 · (𝐼‘𝑋)) = (-𝑦 · (𝐼‘𝑋))) |
| 14 | | oveq1 6657 |
. . . . . . 7
⊢ (𝑥 = -𝑦 → (𝑥 · 𝑋) = (-𝑦 · 𝑋)) |
| 15 | 14 | fveq2d 6195 |
. . . . . 6
⊢ (𝑥 = -𝑦 → (𝐼‘(𝑥 · 𝑋)) = (𝐼‘(-𝑦 · 𝑋))) |
| 16 | 13, 15 | eqeq12d 2637 |
. . . . 5
⊢ (𝑥 = -𝑦 → ((𝑥 · (𝐼‘𝑋)) = (𝐼‘(𝑥 · 𝑋)) ↔ (-𝑦 · (𝐼‘𝑋)) = (𝐼‘(-𝑦 · 𝑋)))) |
| 17 | | oveq1 6657 |
. . . . . 6
⊢ (𝑥 = 𝑁 → (𝑥 · (𝐼‘𝑋)) = (𝑁 · (𝐼‘𝑋))) |
| 18 | | oveq1 6657 |
. . . . . . 7
⊢ (𝑥 = 𝑁 → (𝑥 · 𝑋) = (𝑁 · 𝑋)) |
| 19 | 18 | fveq2d 6195 |
. . . . . 6
⊢ (𝑥 = 𝑁 → (𝐼‘(𝑥 · 𝑋)) = (𝐼‘(𝑁 · 𝑋))) |
| 20 | 17, 19 | eqeq12d 2637 |
. . . . 5
⊢ (𝑥 = 𝑁 → ((𝑥 · (𝐼‘𝑋)) = (𝐼‘(𝑥 · 𝑋)) ↔ (𝑁 · (𝐼‘𝑋)) = (𝐼‘(𝑁 · 𝑋)))) |
| 21 | | eqid 2622 |
. . . . . . . . 9
⊢
(0g‘𝐺) = (0g‘𝐺) |
| 22 | | mulginvcom.i |
. . . . . . . . 9
⊢ 𝐼 = (invg‘𝐺) |
| 23 | 21, 22 | grpinvid 17476 |
. . . . . . . 8
⊢ (𝐺 ∈ Grp → (𝐼‘(0g‘𝐺)) = (0g‘𝐺)) |
| 24 | 23 | eqcomd 2628 |
. . . . . . 7
⊢ (𝐺 ∈ Grp →
(0g‘𝐺) =
(𝐼‘(0g‘𝐺))) |
| 25 | 24 | adantr 481 |
. . . . . 6
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → (0g‘𝐺) = (𝐼‘(0g‘𝐺))) |
| 26 | | mulginvcom.b |
. . . . . . . 8
⊢ 𝐵 = (Base‘𝐺) |
| 27 | 26, 22 | grpinvcl 17467 |
. . . . . . 7
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → (𝐼‘𝑋) ∈ 𝐵) |
| 28 | | mulginvcom.t |
. . . . . . . 8
⊢ · =
(.g‘𝐺) |
| 29 | 26, 21, 28 | mulg0 17546 |
. . . . . . 7
⊢ ((𝐼‘𝑋) ∈ 𝐵 → (0 · (𝐼‘𝑋)) = (0g‘𝐺)) |
| 30 | 27, 29 | syl 17 |
. . . . . 6
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → (0 · (𝐼‘𝑋)) = (0g‘𝐺)) |
| 31 | 26, 21, 28 | mulg0 17546 |
. . . . . . . 8
⊢ (𝑋 ∈ 𝐵 → (0 · 𝑋) = (0g‘𝐺)) |
| 32 | 31 | adantl 482 |
. . . . . . 7
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → (0 · 𝑋) = (0g‘𝐺)) |
| 33 | 32 | fveq2d 6195 |
. . . . . 6
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → (𝐼‘(0 · 𝑋)) = (𝐼‘(0g‘𝐺))) |
| 34 | 25, 30, 33 | 3eqtr4d 2666 |
. . . . 5
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → (0 · (𝐼‘𝑋)) = (𝐼‘(0 · 𝑋))) |
| 35 | | oveq2 6658 |
. . . . . . . . . 10
⊢ ((𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋)) → ((𝐼‘𝑋)(+g‘𝐺)(𝑦 · (𝐼‘𝑋))) = ((𝐼‘𝑋)(+g‘𝐺)(𝐼‘(𝑦 · 𝑋)))) |
| 36 | 35 | adantl 482 |
. . . . . . . . 9
⊢ (((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) ∧ (𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋))) → ((𝐼‘𝑋)(+g‘𝐺)(𝑦 · (𝐼‘𝑋))) = ((𝐼‘𝑋)(+g‘𝐺)(𝐼‘(𝑦 · 𝑋)))) |
| 37 | | grpmnd 17429 |
. . . . . . . . . . . . 13
⊢ (𝐺 ∈ Grp → 𝐺 ∈ Mnd) |
| 38 | 37 | 3ad2ant1 1082 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → 𝐺 ∈ Mnd) |
| 39 | | simp2 1062 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → 𝑦 ∈ ℕ0) |
| 40 | 27 | 3adant2 1080 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → (𝐼‘𝑋) ∈ 𝐵) |
| 41 | | eqid 2622 |
. . . . . . . . . . . . 13
⊢
(+g‘𝐺) = (+g‘𝐺) |
| 42 | 26, 28, 41 | mulgnn0p1 17552 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ Mnd ∧ 𝑦 ∈ ℕ0
∧ (𝐼‘𝑋) ∈ 𝐵) → ((𝑦 + 1) · (𝐼‘𝑋)) = ((𝑦 · (𝐼‘𝑋))(+g‘𝐺)(𝐼‘𝑋))) |
| 43 | 38, 39, 40, 42 | syl3anc 1326 |
. . . . . . . . . . 11
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → ((𝑦 + 1) · (𝐼‘𝑋)) = ((𝑦 · (𝐼‘𝑋))(+g‘𝐺)(𝐼‘𝑋))) |
| 44 | | simp1 1061 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → 𝐺 ∈ Grp) |
| 45 | | nn0z 11400 |
. . . . . . . . . . . . 13
⊢ (𝑦 ∈ ℕ0
→ 𝑦 ∈
ℤ) |
| 46 | 45 | 3ad2ant2 1083 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → 𝑦 ∈ ℤ) |
| 47 | 26, 28, 41 | mulgaddcom 17564 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℤ ∧ (𝐼‘𝑋) ∈ 𝐵) → ((𝑦 · (𝐼‘𝑋))(+g‘𝐺)(𝐼‘𝑋)) = ((𝐼‘𝑋)(+g‘𝐺)(𝑦 · (𝐼‘𝑋)))) |
| 48 | 44, 46, 40, 47 | syl3anc 1326 |
. . . . . . . . . . 11
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → ((𝑦 · (𝐼‘𝑋))(+g‘𝐺)(𝐼‘𝑋)) = ((𝐼‘𝑋)(+g‘𝐺)(𝑦 · (𝐼‘𝑋)))) |
| 49 | 43, 48 | eqtrd 2656 |
. . . . . . . . . 10
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → ((𝑦 + 1) · (𝐼‘𝑋)) = ((𝐼‘𝑋)(+g‘𝐺)(𝑦 · (𝐼‘𝑋)))) |
| 50 | 49 | adantr 481 |
. . . . . . . . 9
⊢ (((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) ∧ (𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋))) → ((𝑦 + 1) · (𝐼‘𝑋)) = ((𝐼‘𝑋)(+g‘𝐺)(𝑦 · (𝐼‘𝑋)))) |
| 51 | 26, 28, 41 | mulgnn0p1 17552 |
. . . . . . . . . . . . 13
⊢ ((𝐺 ∈ Mnd ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → ((𝑦 + 1) · 𝑋) = ((𝑦 · 𝑋)(+g‘𝐺)𝑋)) |
| 52 | 37, 51 | syl3an1 1359 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → ((𝑦 + 1) · 𝑋) = ((𝑦 · 𝑋)(+g‘𝐺)𝑋)) |
| 53 | 52 | fveq2d 6195 |
. . . . . . . . . . 11
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → (𝐼‘((𝑦 + 1) · 𝑋)) = (𝐼‘((𝑦 · 𝑋)(+g‘𝐺)𝑋))) |
| 54 | 26, 28 | mulgcl 17559 |
. . . . . . . . . . . . 13
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℤ ∧ 𝑋 ∈ 𝐵) → (𝑦 · 𝑋) ∈ 𝐵) |
| 55 | 45, 54 | syl3an2 1360 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → (𝑦 · 𝑋) ∈ 𝐵) |
| 56 | 26, 41, 22 | grpinvadd 17493 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ Grp ∧ (𝑦 · 𝑋) ∈ 𝐵 ∧ 𝑋 ∈ 𝐵) → (𝐼‘((𝑦 · 𝑋)(+g‘𝐺)𝑋)) = ((𝐼‘𝑋)(+g‘𝐺)(𝐼‘(𝑦 · 𝑋)))) |
| 57 | 55, 56 | syld3an2 1373 |
. . . . . . . . . . 11
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → (𝐼‘((𝑦 · 𝑋)(+g‘𝐺)𝑋)) = ((𝐼‘𝑋)(+g‘𝐺)(𝐼‘(𝑦 · 𝑋)))) |
| 58 | 53, 57 | eqtrd 2656 |
. . . . . . . . . 10
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) → (𝐼‘((𝑦 + 1) · 𝑋)) = ((𝐼‘𝑋)(+g‘𝐺)(𝐼‘(𝑦 · 𝑋)))) |
| 59 | 58 | adantr 481 |
. . . . . . . . 9
⊢ (((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) ∧ (𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋))) → (𝐼‘((𝑦 + 1) · 𝑋)) = ((𝐼‘𝑋)(+g‘𝐺)(𝐼‘(𝑦 · 𝑋)))) |
| 60 | 36, 50, 59 | 3eqtr4d 2666 |
. . . . . . . 8
⊢ (((𝐺 ∈ Grp ∧ 𝑦 ∈ ℕ0
∧ 𝑋 ∈ 𝐵) ∧ (𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋))) → ((𝑦 + 1) · (𝐼‘𝑋)) = (𝐼‘((𝑦 + 1) · 𝑋))) |
| 61 | 60 | 3exp1 1283 |
. . . . . . 7
⊢ (𝐺 ∈ Grp → (𝑦 ∈ ℕ0
→ (𝑋 ∈ 𝐵 → ((𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋)) → ((𝑦 + 1) · (𝐼‘𝑋)) = (𝐼‘((𝑦 + 1) · 𝑋)))))) |
| 62 | 61 | com23 86 |
. . . . . 6
⊢ (𝐺 ∈ Grp → (𝑋 ∈ 𝐵 → (𝑦 ∈ ℕ0 → ((𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋)) → ((𝑦 + 1) · (𝐼‘𝑋)) = (𝐼‘((𝑦 + 1) · 𝑋)))))) |
| 63 | 62 | imp 445 |
. . . . 5
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → (𝑦 ∈ ℕ0 → ((𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋)) → ((𝑦 + 1) · (𝐼‘𝑋)) = (𝐼‘((𝑦 + 1) · 𝑋))))) |
| 64 | | nnz 11399 |
. . . . . 6
⊢ (𝑦 ∈ ℕ → 𝑦 ∈
ℤ) |
| 65 | 27 | 3adant2 1080 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℤ ∧ 𝑋 ∈ 𝐵) → (𝐼‘𝑋) ∈ 𝐵) |
| 66 | 26, 28, 22 | mulgneg 17560 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℤ ∧ (𝐼‘𝑋) ∈ 𝐵) → (-𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · (𝐼‘𝑋)))) |
| 67 | 65, 66 | syld3an3 1371 |
. . . . . . . . . . 11
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℤ ∧ 𝑋 ∈ 𝐵) → (-𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · (𝐼‘𝑋)))) |
| 68 | 67 | adantr 481 |
. . . . . . . . . 10
⊢ (((𝐺 ∈ Grp ∧ 𝑦 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ (𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋))) → (-𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · (𝐼‘𝑋)))) |
| 69 | 26, 28, 22 | mulgneg 17560 |
. . . . . . . . . . . . 13
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ ℤ ∧ 𝑋 ∈ 𝐵) → (-𝑦 · 𝑋) = (𝐼‘(𝑦 · 𝑋))) |
| 70 | 69 | adantr 481 |
. . . . . . . . . . . 12
⊢ (((𝐺 ∈ Grp ∧ 𝑦 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ (𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋))) → (-𝑦 · 𝑋) = (𝐼‘(𝑦 · 𝑋))) |
| 71 | | simpr 477 |
. . . . . . . . . . . 12
⊢ (((𝐺 ∈ Grp ∧ 𝑦 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ (𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋))) → (𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋))) |
| 72 | 70, 71 | eqtr4d 2659 |
. . . . . . . . . . 11
⊢ (((𝐺 ∈ Grp ∧ 𝑦 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ (𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋))) → (-𝑦 · 𝑋) = (𝑦 · (𝐼‘𝑋))) |
| 73 | 72 | fveq2d 6195 |
. . . . . . . . . 10
⊢ (((𝐺 ∈ Grp ∧ 𝑦 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ (𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋))) → (𝐼‘(-𝑦 · 𝑋)) = (𝐼‘(𝑦 · (𝐼‘𝑋)))) |
| 74 | 68, 73 | eqtr4d 2659 |
. . . . . . . . 9
⊢ (((𝐺 ∈ Grp ∧ 𝑦 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ (𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋))) → (-𝑦 · (𝐼‘𝑋)) = (𝐼‘(-𝑦 · 𝑋))) |
| 75 | 74 | 3exp1 1283 |
. . . . . . . 8
⊢ (𝐺 ∈ Grp → (𝑦 ∈ ℤ → (𝑋 ∈ 𝐵 → ((𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋)) → (-𝑦 · (𝐼‘𝑋)) = (𝐼‘(-𝑦 · 𝑋)))))) |
| 76 | 75 | com23 86 |
. . . . . . 7
⊢ (𝐺 ∈ Grp → (𝑋 ∈ 𝐵 → (𝑦 ∈ ℤ → ((𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋)) → (-𝑦 · (𝐼‘𝑋)) = (𝐼‘(-𝑦 · 𝑋)))))) |
| 77 | 76 | imp 445 |
. . . . . 6
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → (𝑦 ∈ ℤ → ((𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋)) → (-𝑦 · (𝐼‘𝑋)) = (𝐼‘(-𝑦 · 𝑋))))) |
| 78 | 64, 77 | syl5 34 |
. . . . 5
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → (𝑦 ∈ ℕ → ((𝑦 · (𝐼‘𝑋)) = (𝐼‘(𝑦 · 𝑋)) → (-𝑦 · (𝐼‘𝑋)) = (𝐼‘(-𝑦 · 𝑋))))) |
| 79 | 4, 8, 12, 16, 20, 34, 63, 78 | zindd 11478 |
. . . 4
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → (𝑁 ∈ ℤ → (𝑁 · (𝐼‘𝑋)) = (𝐼‘(𝑁 · 𝑋)))) |
| 80 | 79 | ex 450 |
. . 3
⊢ (𝐺 ∈ Grp → (𝑋 ∈ 𝐵 → (𝑁 ∈ ℤ → (𝑁 · (𝐼‘𝑋)) = (𝐼‘(𝑁 · 𝑋))))) |
| 81 | 80 | com23 86 |
. 2
⊢ (𝐺 ∈ Grp → (𝑁 ∈ ℤ → (𝑋 ∈ 𝐵 → (𝑁 · (𝐼‘𝑋)) = (𝐼‘(𝑁 · 𝑋))))) |
| 82 | 81 | 3imp 1256 |
1
⊢ ((𝐺 ∈ Grp ∧ 𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) → (𝑁 · (𝐼‘𝑋)) = (𝐼‘(𝑁 · 𝑋))) |