Proof of Theorem flt4lem6
Step | Hyp | Ref
| Expression |
1 | | flt4lem6.a |
. . . 4
⊢ (𝜑 → 𝐴 ∈ ℕ) |
2 | | flt4lem6.b |
. . . . 5
⊢ (𝜑 → 𝐵 ∈ ℕ) |
3 | 2 | nnzd 12425 |
. . . 4
⊢ (𝜑 → 𝐵 ∈ ℤ) |
4 | | divgcdnn 16222 |
. . . 4
⊢ ((𝐴 ∈ ℕ ∧ 𝐵 ∈ ℤ) → (𝐴 / (𝐴 gcd 𝐵)) ∈ ℕ) |
5 | 1, 3, 4 | syl2anc 584 |
. . 3
⊢ (𝜑 → (𝐴 / (𝐴 gcd 𝐵)) ∈ ℕ) |
6 | 1 | nnzd 12425 |
. . . 4
⊢ (𝜑 → 𝐴 ∈ ℤ) |
7 | | divgcdnnr 16223 |
. . . 4
⊢ ((𝐵 ∈ ℕ ∧ 𝐴 ∈ ℤ) → (𝐵 / (𝐴 gcd 𝐵)) ∈ ℕ) |
8 | 2, 6, 7 | syl2anc 584 |
. . 3
⊢ (𝜑 → (𝐵 / (𝐴 gcd 𝐵)) ∈ ℕ) |
9 | | flt4lem6.1 |
. . . . . . 7
⊢ (𝜑 → ((𝐴↑4) + (𝐵↑4)) = (𝐶↑2)) |
10 | | gcdnncl 16214 |
. . . . . . . . . 10
⊢ ((𝐴 ∈ ℕ ∧ 𝐵 ∈ ℕ) → (𝐴 gcd 𝐵) ∈ ℕ) |
11 | 1, 2, 10 | syl2anc 584 |
. . . . . . . . 9
⊢ (𝜑 → (𝐴 gcd 𝐵) ∈ ℕ) |
12 | 11 | nncnd 11989 |
. . . . . . . 8
⊢ (𝜑 → (𝐴 gcd 𝐵) ∈ ℂ) |
13 | 12 | flt4lem 40482 |
. . . . . . 7
⊢ (𝜑 → ((𝐴 gcd 𝐵)↑4) = (((𝐴 gcd 𝐵)↑2)↑2)) |
14 | 9, 13 | oveq12d 7293 |
. . . . . 6
⊢ (𝜑 → (((𝐴↑4) + (𝐵↑4)) / ((𝐴 gcd 𝐵)↑4)) = ((𝐶↑2) / (((𝐴 gcd 𝐵)↑2)↑2))) |
15 | 1 | nncnd 11989 |
. . . . . . . . 9
⊢ (𝜑 → 𝐴 ∈ ℂ) |
16 | 11 | nnne0d 12023 |
. . . . . . . . 9
⊢ (𝜑 → (𝐴 gcd 𝐵) ≠ 0) |
17 | | 4nn0 12252 |
. . . . . . . . . 10
⊢ 4 ∈
ℕ0 |
18 | 17 | a1i 11 |
. . . . . . . . 9
⊢ (𝜑 → 4 ∈
ℕ0) |
19 | 15, 12, 16, 18 | expdivd 13878 |
. . . . . . . 8
⊢ (𝜑 → ((𝐴 / (𝐴 gcd 𝐵))↑4) = ((𝐴↑4) / ((𝐴 gcd 𝐵)↑4))) |
20 | 2 | nncnd 11989 |
. . . . . . . . 9
⊢ (𝜑 → 𝐵 ∈ ℂ) |
21 | 20, 12, 16, 18 | expdivd 13878 |
. . . . . . . 8
⊢ (𝜑 → ((𝐵 / (𝐴 gcd 𝐵))↑4) = ((𝐵↑4) / ((𝐴 gcd 𝐵)↑4))) |
22 | 19, 21 | oveq12d 7293 |
. . . . . . 7
⊢ (𝜑 → (((𝐴 / (𝐴 gcd 𝐵))↑4) + ((𝐵 / (𝐴 gcd 𝐵))↑4)) = (((𝐴↑4) / ((𝐴 gcd 𝐵)↑4)) + ((𝐵↑4) / ((𝐴 gcd 𝐵)↑4)))) |
23 | 15, 18 | expcld 13864 |
. . . . . . . 8
⊢ (𝜑 → (𝐴↑4) ∈ ℂ) |
24 | 20, 18 | expcld 13864 |
. . . . . . . 8
⊢ (𝜑 → (𝐵↑4) ∈ ℂ) |
25 | 12, 18 | expcld 13864 |
. . . . . . . 8
⊢ (𝜑 → ((𝐴 gcd 𝐵)↑4) ∈ ℂ) |
26 | 11, 18 | nnexpcld 13960 |
. . . . . . . . 9
⊢ (𝜑 → ((𝐴 gcd 𝐵)↑4) ∈ ℕ) |
27 | 26 | nnne0d 12023 |
. . . . . . . 8
⊢ (𝜑 → ((𝐴 gcd 𝐵)↑4) ≠ 0) |
28 | 23, 24, 25, 27 | divdird 11789 |
. . . . . . 7
⊢ (𝜑 → (((𝐴↑4) + (𝐵↑4)) / ((𝐴 gcd 𝐵)↑4)) = (((𝐴↑4) / ((𝐴 gcd 𝐵)↑4)) + ((𝐵↑4) / ((𝐴 gcd 𝐵)↑4)))) |
29 | 22, 28 | eqtr4d 2781 |
. . . . . 6
⊢ (𝜑 → (((𝐴 / (𝐴 gcd 𝐵))↑4) + ((𝐵 / (𝐴 gcd 𝐵))↑4)) = (((𝐴↑4) + (𝐵↑4)) / ((𝐴 gcd 𝐵)↑4))) |
30 | | flt4lem6.c |
. . . . . . . 8
⊢ (𝜑 → 𝐶 ∈ ℕ) |
31 | 30 | nncnd 11989 |
. . . . . . 7
⊢ (𝜑 → 𝐶 ∈ ℂ) |
32 | 11 | nnsqcld 13959 |
. . . . . . . 8
⊢ (𝜑 → ((𝐴 gcd 𝐵)↑2) ∈ ℕ) |
33 | 32 | nncnd 11989 |
. . . . . . 7
⊢ (𝜑 → ((𝐴 gcd 𝐵)↑2) ∈ ℂ) |
34 | 32 | nnne0d 12023 |
. . . . . . 7
⊢ (𝜑 → ((𝐴 gcd 𝐵)↑2) ≠ 0) |
35 | 31, 33, 34 | sqdivd 13877 |
. . . . . 6
⊢ (𝜑 → ((𝐶 / ((𝐴 gcd 𝐵)↑2))↑2) = ((𝐶↑2) / (((𝐴 gcd 𝐵)↑2)↑2))) |
36 | 14, 29, 35 | 3eqtr4d 2788 |
. . . . 5
⊢ (𝜑 → (((𝐴 / (𝐴 gcd 𝐵))↑4) + ((𝐵 / (𝐴 gcd 𝐵))↑4)) = ((𝐶 / ((𝐴 gcd 𝐵)↑2))↑2)) |
37 | 5, 18 | nnexpcld 13960 |
. . . . . . 7
⊢ (𝜑 → ((𝐴 / (𝐴 gcd 𝐵))↑4) ∈ ℕ) |
38 | 8, 18 | nnexpcld 13960 |
. . . . . . 7
⊢ (𝜑 → ((𝐵 / (𝐴 gcd 𝐵))↑4) ∈ ℕ) |
39 | 37, 38 | nnaddcld 12025 |
. . . . . 6
⊢ (𝜑 → (((𝐴 / (𝐴 gcd 𝐵))↑4) + ((𝐵 / (𝐴 gcd 𝐵))↑4)) ∈ ℕ) |
40 | 39 | nnzd 12425 |
. . . . 5
⊢ (𝜑 → (((𝐴 / (𝐴 gcd 𝐵))↑4) + ((𝐵 / (𝐴 gcd 𝐵))↑4)) ∈ ℤ) |
41 | 36, 40 | eqeltrrd 2840 |
. . . 4
⊢ (𝜑 → ((𝐶 / ((𝐴 gcd 𝐵)↑2))↑2) ∈
ℤ) |
42 | 30 | nnzd 12425 |
. . . . 5
⊢ (𝜑 → 𝐶 ∈ ℤ) |
43 | | znq 12692 |
. . . . 5
⊢ ((𝐶 ∈ ℤ ∧ ((𝐴 gcd 𝐵)↑2) ∈ ℕ) → (𝐶 / ((𝐴 gcd 𝐵)↑2)) ∈ ℚ) |
44 | 42, 32, 43 | syl2anc 584 |
. . . 4
⊢ (𝜑 → (𝐶 / ((𝐴 gcd 𝐵)↑2)) ∈ ℚ) |
45 | 30 | nnred 11988 |
. . . . 5
⊢ (𝜑 → 𝐶 ∈ ℝ) |
46 | 32 | nnred 11988 |
. . . . 5
⊢ (𝜑 → ((𝐴 gcd 𝐵)↑2) ∈ ℝ) |
47 | 30 | nngt0d 12022 |
. . . . 5
⊢ (𝜑 → 0 < 𝐶) |
48 | 32 | nngt0d 12022 |
. . . . 5
⊢ (𝜑 → 0 < ((𝐴 gcd 𝐵)↑2)) |
49 | 45, 46, 47, 48 | divgt0d 11910 |
. . . 4
⊢ (𝜑 → 0 < (𝐶 / ((𝐴 gcd 𝐵)↑2))) |
50 | 41, 44, 49 | posqsqznn 40343 |
. . 3
⊢ (𝜑 → (𝐶 / ((𝐴 gcd 𝐵)↑2)) ∈ ℕ) |
51 | 5, 8, 50 | 3jca 1127 |
. 2
⊢ (𝜑 → ((𝐴 / (𝐴 gcd 𝐵)) ∈ ℕ ∧ (𝐵 / (𝐴 gcd 𝐵)) ∈ ℕ ∧ (𝐶 / ((𝐴 gcd 𝐵)↑2)) ∈ ℕ)) |
52 | 51, 36 | jca 512 |
1
⊢ (𝜑 → (((𝐴 / (𝐴 gcd 𝐵)) ∈ ℕ ∧ (𝐵 / (𝐴 gcd 𝐵)) ∈ ℕ ∧ (𝐶 / ((𝐴 gcd 𝐵)↑2)) ∈ ℕ) ∧ (((𝐴 / (𝐴 gcd 𝐵))↑4) + ((𝐵 / (𝐴 gcd 𝐵))↑4)) = ((𝐶 / ((𝐴 gcd 𝐵)↑2))↑2))) |