Proof of Theorem elnn0z
Step | Hyp | Ref
| Expression |
1 | | elnn0 12165 |
. 2
⊢ (𝑁 ∈ ℕ0
↔ (𝑁 ∈ ℕ
∨ 𝑁 =
0)) |
2 | | elnnz 12259 |
. . 3
⊢ (𝑁 ∈ ℕ ↔ (𝑁 ∈ ℤ ∧ 0 <
𝑁)) |
3 | | eqcom 2745 |
. . 3
⊢ (𝑁 = 0 ↔ 0 = 𝑁) |
4 | 2, 3 | orbi12i 911 |
. 2
⊢ ((𝑁 ∈ ℕ ∨ 𝑁 = 0) ↔ ((𝑁 ∈ ℤ ∧ 0 < 𝑁) ∨ 0 = 𝑁)) |
5 | | id 22 |
. . . . . 6
⊢ (𝑁 ∈ ℤ → 𝑁 ∈
ℤ) |
6 | | 0z 12260 |
. . . . . . 7
⊢ 0 ∈
ℤ |
7 | | eleq1 2826 |
. . . . . . 7
⊢ (0 =
𝑁 → (0 ∈ ℤ
↔ 𝑁 ∈
ℤ)) |
8 | 6, 7 | mpbii 232 |
. . . . . 6
⊢ (0 =
𝑁 → 𝑁 ∈ ℤ) |
9 | 5, 8 | jaoi 853 |
. . . . 5
⊢ ((𝑁 ∈ ℤ ∨ 0 = 𝑁) → 𝑁 ∈ ℤ) |
10 | | orc 863 |
. . . . 5
⊢ (𝑁 ∈ ℤ → (𝑁 ∈ ℤ ∨ 0 = 𝑁)) |
11 | 9, 10 | impbii 208 |
. . . 4
⊢ ((𝑁 ∈ ℤ ∨ 0 = 𝑁) ↔ 𝑁 ∈ ℤ) |
12 | 11 | anbi1i 623 |
. . 3
⊢ (((𝑁 ∈ ℤ ∨ 0 = 𝑁) ∧ (0 < 𝑁 ∨ 0 = 𝑁)) ↔ (𝑁 ∈ ℤ ∧ (0 < 𝑁 ∨ 0 = 𝑁))) |
13 | | ordir 1003 |
. . 3
⊢ (((𝑁 ∈ ℤ ∧ 0 <
𝑁) ∨ 0 = 𝑁) ↔ ((𝑁 ∈ ℤ ∨ 0 = 𝑁) ∧ (0 < 𝑁 ∨ 0 = 𝑁))) |
14 | | 0re 10908 |
. . . . 5
⊢ 0 ∈
ℝ |
15 | | zre 12253 |
. . . . 5
⊢ (𝑁 ∈ ℤ → 𝑁 ∈
ℝ) |
16 | | leloe 10992 |
. . . . 5
⊢ ((0
∈ ℝ ∧ 𝑁
∈ ℝ) → (0 ≤ 𝑁 ↔ (0 < 𝑁 ∨ 0 = 𝑁))) |
17 | 14, 15, 16 | sylancr 586 |
. . . 4
⊢ (𝑁 ∈ ℤ → (0 ≤
𝑁 ↔ (0 < 𝑁 ∨ 0 = 𝑁))) |
18 | 17 | pm5.32i 574 |
. . 3
⊢ ((𝑁 ∈ ℤ ∧ 0 ≤
𝑁) ↔ (𝑁 ∈ ℤ ∧ (0 <
𝑁 ∨ 0 = 𝑁))) |
19 | 12, 13, 18 | 3bitr4i 302 |
. 2
⊢ (((𝑁 ∈ ℤ ∧ 0 <
𝑁) ∨ 0 = 𝑁) ↔ (𝑁 ∈ ℤ ∧ 0 ≤ 𝑁)) |
20 | 1, 4, 19 | 3bitri 296 |
1
⊢ (𝑁 ∈ ℕ0
↔ (𝑁 ∈ ℤ
∧ 0 ≤ 𝑁)) |