Proof of Theorem dvdssq
Step | Hyp | Ref
| Expression |
1 | | 0z 9198 |
. . . 4
⊢ 0 ∈
ℤ |
2 | | zdceq 9262 |
. . . 4
⊢ ((𝑀 ∈ ℤ ∧ 0 ∈
ℤ) → DECID 𝑀 = 0) |
3 | 1, 2 | mpan2 422 |
. . 3
⊢ (𝑀 ∈ ℤ →
DECID 𝑀 =
0) |
4 | | exmiddc 826 |
. . 3
⊢
(DECID 𝑀 = 0 → (𝑀 = 0 ∨ ¬ 𝑀 = 0)) |
5 | | 0dvds 11747 |
. . . . . . . 8
⊢ (𝑁 ∈ ℤ → (0
∥ 𝑁 ↔ 𝑁 = 0)) |
6 | | zcn 9192 |
. . . . . . . . 9
⊢ (𝑁 ∈ ℤ → 𝑁 ∈
ℂ) |
7 | | sqeq0 10514 |
. . . . . . . . 9
⊢ (𝑁 ∈ ℂ → ((𝑁↑2) = 0 ↔ 𝑁 = 0)) |
8 | 6, 7 | syl 14 |
. . . . . . . 8
⊢ (𝑁 ∈ ℤ → ((𝑁↑2) = 0 ↔ 𝑁 = 0)) |
9 | 5, 8 | bitr4d 190 |
. . . . . . 7
⊢ (𝑁 ∈ ℤ → (0
∥ 𝑁 ↔ (𝑁↑2) = 0)) |
10 | | zsqcl 10521 |
. . . . . . . 8
⊢ (𝑁 ∈ ℤ → (𝑁↑2) ∈
ℤ) |
11 | | 0dvds 11747 |
. . . . . . . 8
⊢ ((𝑁↑2) ∈ ℤ →
(0 ∥ (𝑁↑2)
↔ (𝑁↑2) =
0)) |
12 | 10, 11 | syl 14 |
. . . . . . 7
⊢ (𝑁 ∈ ℤ → (0
∥ (𝑁↑2) ↔
(𝑁↑2) =
0)) |
13 | 9, 12 | bitr4d 190 |
. . . . . 6
⊢ (𝑁 ∈ ℤ → (0
∥ 𝑁 ↔ 0 ∥
(𝑁↑2))) |
14 | 13 | adantl 275 |
. . . . 5
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (0
∥ 𝑁 ↔ 0 ∥
(𝑁↑2))) |
15 | | breq1 3984 |
. . . . . 6
⊢ (𝑀 = 0 → (𝑀 ∥ 𝑁 ↔ 0 ∥ 𝑁)) |
16 | | sq0i 10542 |
. . . . . . 7
⊢ (𝑀 = 0 → (𝑀↑2) = 0) |
17 | 16 | breq1d 3991 |
. . . . . 6
⊢ (𝑀 = 0 → ((𝑀↑2) ∥ (𝑁↑2) ↔ 0 ∥ (𝑁↑2))) |
18 | 15, 17 | bibi12d 234 |
. . . . 5
⊢ (𝑀 = 0 → ((𝑀 ∥ 𝑁 ↔ (𝑀↑2) ∥ (𝑁↑2)) ↔ (0 ∥ 𝑁 ↔ 0 ∥ (𝑁↑2)))) |
19 | 14, 18 | syl5ibr 155 |
. . . 4
⊢ (𝑀 = 0 → ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 ∥ 𝑁 ↔ (𝑀↑2) ∥ (𝑁↑2)))) |
20 | | df-ne 2336 |
. . . . 5
⊢ (𝑀 ≠ 0 ↔ ¬ 𝑀 = 0) |
21 | | nnabscl 11038 |
. . . . . . . . 9
⊢ ((𝑀 ∈ ℤ ∧ 𝑀 ≠ 0) → (abs‘𝑀) ∈
ℕ) |
22 | | zdceq 9262 |
. . . . . . . . . . . 12
⊢ ((𝑁 ∈ ℤ ∧ 0 ∈
ℤ) → DECID 𝑁 = 0) |
23 | 1, 22 | mpan2 422 |
. . . . . . . . . . 11
⊢ (𝑁 ∈ ℤ →
DECID 𝑁 =
0) |
24 | | exmiddc 826 |
. . . . . . . . . . 11
⊢
(DECID 𝑁 = 0 → (𝑁 = 0 ∨ ¬ 𝑁 = 0)) |
25 | | nnz 9206 |
. . . . . . . . . . . . . . 15
⊢
((abs‘𝑀)
∈ ℕ → (abs‘𝑀) ∈ ℤ) |
26 | | dvds0 11742 |
. . . . . . . . . . . . . . . 16
⊢
((abs‘𝑀)
∈ ℤ → (abs‘𝑀) ∥ 0) |
27 | | zsqcl 10521 |
. . . . . . . . . . . . . . . . 17
⊢
((abs‘𝑀)
∈ ℤ → ((abs‘𝑀)↑2) ∈ ℤ) |
28 | | dvds0 11742 |
. . . . . . . . . . . . . . . . 17
⊢
(((abs‘𝑀)↑2) ∈ ℤ →
((abs‘𝑀)↑2)
∥ 0) |
29 | 27, 28 | syl 14 |
. . . . . . . . . . . . . . . 16
⊢
((abs‘𝑀)
∈ ℤ → ((abs‘𝑀)↑2) ∥ 0) |
30 | 26, 29 | 2thd 174 |
. . . . . . . . . . . . . . 15
⊢
((abs‘𝑀)
∈ ℤ → ((abs‘𝑀) ∥ 0 ↔ ((abs‘𝑀)↑2) ∥
0)) |
31 | 25, 30 | syl 14 |
. . . . . . . . . . . . . 14
⊢
((abs‘𝑀)
∈ ℕ → ((abs‘𝑀) ∥ 0 ↔ ((abs‘𝑀)↑2) ∥
0)) |
32 | 31 | adantr 274 |
. . . . . . . . . . . . 13
⊢
(((abs‘𝑀)
∈ ℕ ∧ 𝑁
∈ ℤ) → ((abs‘𝑀) ∥ 0 ↔ ((abs‘𝑀)↑2) ∥
0)) |
33 | | breq2 3985 |
. . . . . . . . . . . . . 14
⊢ (𝑁 = 0 → ((abs‘𝑀) ∥ 𝑁 ↔ (abs‘𝑀) ∥ 0)) |
34 | | sq0i 10542 |
. . . . . . . . . . . . . . 15
⊢ (𝑁 = 0 → (𝑁↑2) = 0) |
35 | 34 | breq2d 3993 |
. . . . . . . . . . . . . 14
⊢ (𝑁 = 0 → (((abs‘𝑀)↑2) ∥ (𝑁↑2) ↔
((abs‘𝑀)↑2)
∥ 0)) |
36 | 33, 35 | bibi12d 234 |
. . . . . . . . . . . . 13
⊢ (𝑁 = 0 → (((abs‘𝑀) ∥ 𝑁 ↔ ((abs‘𝑀)↑2) ∥ (𝑁↑2)) ↔ ((abs‘𝑀) ∥ 0 ↔
((abs‘𝑀)↑2)
∥ 0))) |
37 | 32, 36 | syl5ibr 155 |
. . . . . . . . . . . 12
⊢ (𝑁 = 0 → (((abs‘𝑀) ∈ ℕ ∧ 𝑁 ∈ ℤ) →
((abs‘𝑀) ∥
𝑁 ↔ ((abs‘𝑀)↑2) ∥ (𝑁↑2)))) |
38 | | df-ne 2336 |
. . . . . . . . . . . . 13
⊢ (𝑁 ≠ 0 ↔ ¬ 𝑁 = 0) |
39 | | nnabscl 11038 |
. . . . . . . . . . . . . . . . 17
⊢ ((𝑁 ∈ ℤ ∧ 𝑁 ≠ 0) → (abs‘𝑁) ∈
ℕ) |
40 | | dvdssqlem 11959 |
. . . . . . . . . . . . . . . . 17
⊢
(((abs‘𝑀)
∈ ℕ ∧ (abs‘𝑁) ∈ ℕ) → ((abs‘𝑀) ∥ (abs‘𝑁) ↔ ((abs‘𝑀)↑2) ∥
((abs‘𝑁)↑2))) |
41 | 39, 40 | sylan2 284 |
. . . . . . . . . . . . . . . 16
⊢
(((abs‘𝑀)
∈ ℕ ∧ (𝑁
∈ ℤ ∧ 𝑁 ≠
0)) → ((abs‘𝑀)
∥ (abs‘𝑁)
↔ ((abs‘𝑀)↑2) ∥ ((abs‘𝑁)↑2))) |
42 | | simpl 108 |
. . . . . . . . . . . . . . . . 17
⊢ ((𝑁 ∈ ℤ ∧ 𝑁 ≠ 0) → 𝑁 ∈
ℤ) |
43 | | dvdsabsb 11746 |
. . . . . . . . . . . . . . . . 17
⊢
(((abs‘𝑀)
∈ ℤ ∧ 𝑁
∈ ℤ) → ((abs‘𝑀) ∥ 𝑁 ↔ (abs‘𝑀) ∥ (abs‘𝑁))) |
44 | 25, 42, 43 | syl2an 287 |
. . . . . . . . . . . . . . . 16
⊢
(((abs‘𝑀)
∈ ℕ ∧ (𝑁
∈ ℤ ∧ 𝑁 ≠
0)) → ((abs‘𝑀)
∥ 𝑁 ↔
(abs‘𝑀) ∥
(abs‘𝑁))) |
45 | | nnsqcl 10520 |
. . . . . . . . . . . . . . . . . . 19
⊢
((abs‘𝑀)
∈ ℕ → ((abs‘𝑀)↑2) ∈ ℕ) |
46 | 45 | nnzd 9308 |
. . . . . . . . . . . . . . . . . 18
⊢
((abs‘𝑀)
∈ ℕ → ((abs‘𝑀)↑2) ∈ ℤ) |
47 | 10 | adantr 274 |
. . . . . . . . . . . . . . . . . 18
⊢ ((𝑁 ∈ ℤ ∧ 𝑁 ≠ 0) → (𝑁↑2) ∈
ℤ) |
48 | | dvdsabsb 11746 |
. . . . . . . . . . . . . . . . . 18
⊢
((((abs‘𝑀)↑2) ∈ ℤ ∧ (𝑁↑2) ∈ ℤ) →
(((abs‘𝑀)↑2)
∥ (𝑁↑2) ↔
((abs‘𝑀)↑2)
∥ (abs‘(𝑁↑2)))) |
49 | 46, 47, 48 | syl2an 287 |
. . . . . . . . . . . . . . . . 17
⊢
(((abs‘𝑀)
∈ ℕ ∧ (𝑁
∈ ℤ ∧ 𝑁 ≠
0)) → (((abs‘𝑀)↑2) ∥ (𝑁↑2) ↔ ((abs‘𝑀)↑2) ∥
(abs‘(𝑁↑2)))) |
50 | 6 | adantr 274 |
. . . . . . . . . . . . . . . . . . . 20
⊢ ((𝑁 ∈ ℤ ∧ 𝑁 ≠ 0) → 𝑁 ∈
ℂ) |
51 | | abssq 11019 |
. . . . . . . . . . . . . . . . . . . 20
⊢ (𝑁 ∈ ℂ →
((abs‘𝑁)↑2) =
(abs‘(𝑁↑2))) |
52 | 50, 51 | syl 14 |
. . . . . . . . . . . . . . . . . . 19
⊢ ((𝑁 ∈ ℤ ∧ 𝑁 ≠ 0) →
((abs‘𝑁)↑2) =
(abs‘(𝑁↑2))) |
53 | 52 | breq2d 3993 |
. . . . . . . . . . . . . . . . . 18
⊢ ((𝑁 ∈ ℤ ∧ 𝑁 ≠ 0) →
(((abs‘𝑀)↑2)
∥ ((abs‘𝑁)↑2) ↔ ((abs‘𝑀)↑2) ∥
(abs‘(𝑁↑2)))) |
54 | 53 | adantl 275 |
. . . . . . . . . . . . . . . . 17
⊢
(((abs‘𝑀)
∈ ℕ ∧ (𝑁
∈ ℤ ∧ 𝑁 ≠
0)) → (((abs‘𝑀)↑2) ∥ ((abs‘𝑁)↑2) ↔
((abs‘𝑀)↑2)
∥ (abs‘(𝑁↑2)))) |
55 | 49, 54 | bitr4d 190 |
. . . . . . . . . . . . . . . 16
⊢
(((abs‘𝑀)
∈ ℕ ∧ (𝑁
∈ ℤ ∧ 𝑁 ≠
0)) → (((abs‘𝑀)↑2) ∥ (𝑁↑2) ↔ ((abs‘𝑀)↑2) ∥
((abs‘𝑁)↑2))) |
56 | 41, 44, 55 | 3bitr4d 219 |
. . . . . . . . . . . . . . 15
⊢
(((abs‘𝑀)
∈ ℕ ∧ (𝑁
∈ ℤ ∧ 𝑁 ≠
0)) → ((abs‘𝑀)
∥ 𝑁 ↔
((abs‘𝑀)↑2)
∥ (𝑁↑2))) |
57 | 56 | anassrs 398 |
. . . . . . . . . . . . . 14
⊢
((((abs‘𝑀)
∈ ℕ ∧ 𝑁
∈ ℤ) ∧ 𝑁
≠ 0) → ((abs‘𝑀) ∥ 𝑁 ↔ ((abs‘𝑀)↑2) ∥ (𝑁↑2))) |
58 | 57 | expcom 115 |
. . . . . . . . . . . . 13
⊢ (𝑁 ≠ 0 →
(((abs‘𝑀) ∈
ℕ ∧ 𝑁 ∈
ℤ) → ((abs‘𝑀) ∥ 𝑁 ↔ ((abs‘𝑀)↑2) ∥ (𝑁↑2)))) |
59 | 38, 58 | sylbir 134 |
. . . . . . . . . . . 12
⊢ (¬
𝑁 = 0 →
(((abs‘𝑀) ∈
ℕ ∧ 𝑁 ∈
ℤ) → ((abs‘𝑀) ∥ 𝑁 ↔ ((abs‘𝑀)↑2) ∥ (𝑁↑2)))) |
60 | 37, 59 | jaoi 706 |
. . . . . . . . . . 11
⊢ ((𝑁 = 0 ∨ ¬ 𝑁 = 0) → (((abs‘𝑀) ∈ ℕ ∧ 𝑁 ∈ ℤ) →
((abs‘𝑀) ∥
𝑁 ↔ ((abs‘𝑀)↑2) ∥ (𝑁↑2)))) |
61 | 23, 24, 60 | 3syl 17 |
. . . . . . . . . 10
⊢ (𝑁 ∈ ℤ →
(((abs‘𝑀) ∈
ℕ ∧ 𝑁 ∈
ℤ) → ((abs‘𝑀) ∥ 𝑁 ↔ ((abs‘𝑀)↑2) ∥ (𝑁↑2)))) |
62 | 61 | anabsi7 571 |
. . . . . . . . 9
⊢
(((abs‘𝑀)
∈ ℕ ∧ 𝑁
∈ ℤ) → ((abs‘𝑀) ∥ 𝑁 ↔ ((abs‘𝑀)↑2) ∥ (𝑁↑2))) |
63 | 21, 62 | sylan 281 |
. . . . . . . 8
⊢ (((𝑀 ∈ ℤ ∧ 𝑀 ≠ 0) ∧ 𝑁 ∈ ℤ) → ((abs‘𝑀) ∥ 𝑁 ↔ ((abs‘𝑀)↑2) ∥ (𝑁↑2))) |
64 | | absdvdsb 11745 |
. . . . . . . . 9
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 ∥ 𝑁 ↔ (abs‘𝑀) ∥ 𝑁)) |
65 | 64 | adantlr 469 |
. . . . . . . 8
⊢ (((𝑀 ∈ ℤ ∧ 𝑀 ≠ 0) ∧ 𝑁 ∈ ℤ) → (𝑀 ∥ 𝑁 ↔ (abs‘𝑀) ∥ 𝑁)) |
66 | | zsqcl 10521 |
. . . . . . . . . . 11
⊢ (𝑀 ∈ ℤ → (𝑀↑2) ∈
ℤ) |
67 | 66 | adantr 274 |
. . . . . . . . . 10
⊢ ((𝑀 ∈ ℤ ∧ 𝑀 ≠ 0) → (𝑀↑2) ∈
ℤ) |
68 | | absdvdsb 11745 |
. . . . . . . . . 10
⊢ (((𝑀↑2) ∈ ℤ ∧
(𝑁↑2) ∈ ℤ)
→ ((𝑀↑2) ∥
(𝑁↑2) ↔
(abs‘(𝑀↑2))
∥ (𝑁↑2))) |
69 | 67, 10, 68 | syl2an 287 |
. . . . . . . . 9
⊢ (((𝑀 ∈ ℤ ∧ 𝑀 ≠ 0) ∧ 𝑁 ∈ ℤ) → ((𝑀↑2) ∥ (𝑁↑2) ↔ (abs‘(𝑀↑2)) ∥ (𝑁↑2))) |
70 | | zcn 9192 |
. . . . . . . . . . . . . 14
⊢ (𝑀 ∈ ℤ → 𝑀 ∈
ℂ) |
71 | | abssq 11019 |
. . . . . . . . . . . . . 14
⊢ (𝑀 ∈ ℂ →
((abs‘𝑀)↑2) =
(abs‘(𝑀↑2))) |
72 | 70, 71 | syl 14 |
. . . . . . . . . . . . 13
⊢ (𝑀 ∈ ℤ →
((abs‘𝑀)↑2) =
(abs‘(𝑀↑2))) |
73 | 72 | eqcomd 2171 |
. . . . . . . . . . . 12
⊢ (𝑀 ∈ ℤ →
(abs‘(𝑀↑2)) =
((abs‘𝑀)↑2)) |
74 | 73 | adantr 274 |
. . . . . . . . . . 11
⊢ ((𝑀 ∈ ℤ ∧ 𝑀 ≠ 0) →
(abs‘(𝑀↑2)) =
((abs‘𝑀)↑2)) |
75 | 74 | breq1d 3991 |
. . . . . . . . . 10
⊢ ((𝑀 ∈ ℤ ∧ 𝑀 ≠ 0) →
((abs‘(𝑀↑2))
∥ (𝑁↑2) ↔
((abs‘𝑀)↑2)
∥ (𝑁↑2))) |
76 | 75 | adantr 274 |
. . . . . . . . 9
⊢ (((𝑀 ∈ ℤ ∧ 𝑀 ≠ 0) ∧ 𝑁 ∈ ℤ) → ((abs‘(𝑀↑2)) ∥ (𝑁↑2) ↔
((abs‘𝑀)↑2)
∥ (𝑁↑2))) |
77 | 69, 76 | bitrd 187 |
. . . . . . . 8
⊢ (((𝑀 ∈ ℤ ∧ 𝑀 ≠ 0) ∧ 𝑁 ∈ ℤ) → ((𝑀↑2) ∥ (𝑁↑2) ↔ ((abs‘𝑀)↑2) ∥ (𝑁↑2))) |
78 | 63, 65, 77 | 3bitr4d 219 |
. . . . . . 7
⊢ (((𝑀 ∈ ℤ ∧ 𝑀 ≠ 0) ∧ 𝑁 ∈ ℤ) → (𝑀 ∥ 𝑁 ↔ (𝑀↑2) ∥ (𝑁↑2))) |
79 | 78 | an32s 558 |
. . . . . 6
⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ 𝑀 ≠ 0) → (𝑀 ∥ 𝑁 ↔ (𝑀↑2) ∥ (𝑁↑2))) |
80 | 79 | expcom 115 |
. . . . 5
⊢ (𝑀 ≠ 0 → ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 ∥ 𝑁 ↔ (𝑀↑2) ∥ (𝑁↑2)))) |
81 | 20, 80 | sylbir 134 |
. . . 4
⊢ (¬
𝑀 = 0 → ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 ∥ 𝑁 ↔ (𝑀↑2) ∥ (𝑁↑2)))) |
82 | 19, 81 | jaoi 706 |
. . 3
⊢ ((𝑀 = 0 ∨ ¬ 𝑀 = 0) → ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 ∥ 𝑁 ↔ (𝑀↑2) ∥ (𝑁↑2)))) |
83 | 3, 4, 82 | 3syl 17 |
. 2
⊢ (𝑀 ∈ ℤ → ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 ∥ 𝑁 ↔ (𝑀↑2) ∥ (𝑁↑2)))) |
84 | 83 | anabsi5 569 |
1
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 ∥ 𝑁 ↔ (𝑀↑2) ∥ (𝑁↑2))) |