Proof of Theorem zltp1le
Step | Hyp | Ref
| Expression |
1 | | nnge1 12010 |
. . . 4
⊢ ((𝑁 − 𝑀) ∈ ℕ → 1 ≤ (𝑁 − 𝑀)) |
2 | 1 | a1i 11 |
. . 3
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑁 − 𝑀) ∈ ℕ → 1 ≤ (𝑁 − 𝑀))) |
3 | | znnsub 12375 |
. . 3
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 < 𝑁 ↔ (𝑁 − 𝑀) ∈ ℕ)) |
4 | | zre 12332 |
. . . 4
⊢ (𝑀 ∈ ℤ → 𝑀 ∈
ℝ) |
5 | | zre 12332 |
. . . 4
⊢ (𝑁 ∈ ℤ → 𝑁 ∈
ℝ) |
6 | | 1re 10984 |
. . . . 5
⊢ 1 ∈
ℝ |
7 | | leaddsub2 11461 |
. . . . 5
⊢ ((𝑀 ∈ ℝ ∧ 1 ∈
ℝ ∧ 𝑁 ∈
ℝ) → ((𝑀 + 1)
≤ 𝑁 ↔ 1 ≤ (𝑁 − 𝑀))) |
8 | 6, 7 | mp3an2 1448 |
. . . 4
⊢ ((𝑀 ∈ ℝ ∧ 𝑁 ∈ ℝ) → ((𝑀 + 1) ≤ 𝑁 ↔ 1 ≤ (𝑁 − 𝑀))) |
9 | 4, 5, 8 | syl2an 596 |
. . 3
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑀 + 1) ≤ 𝑁 ↔ 1 ≤ (𝑁 − 𝑀))) |
10 | 2, 3, 9 | 3imtr4d 294 |
. 2
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 < 𝑁 → (𝑀 + 1) ≤ 𝑁)) |
11 | 4 | adantr 481 |
. . . 4
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → 𝑀 ∈
ℝ) |
12 | 11 | ltp1d 11914 |
. . 3
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → 𝑀 < (𝑀 + 1)) |
13 | | peano2re 11157 |
. . . . 5
⊢ (𝑀 ∈ ℝ → (𝑀 + 1) ∈
ℝ) |
14 | 11, 13 | syl 17 |
. . . 4
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 + 1) ∈
ℝ) |
15 | 5 | adantl 482 |
. . . 4
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → 𝑁 ∈
ℝ) |
16 | | ltletr 11076 |
. . . 4
⊢ ((𝑀 ∈ ℝ ∧ (𝑀 + 1) ∈ ℝ ∧ 𝑁 ∈ ℝ) → ((𝑀 < (𝑀 + 1) ∧ (𝑀 + 1) ≤ 𝑁) → 𝑀 < 𝑁)) |
17 | 11, 14, 15, 16 | syl3anc 1370 |
. . 3
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑀 < (𝑀 + 1) ∧ (𝑀 + 1) ≤ 𝑁) → 𝑀 < 𝑁)) |
18 | 12, 17 | mpand 692 |
. 2
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑀 + 1) ≤ 𝑁 → 𝑀 < 𝑁)) |
19 | 10, 18 | impbid 211 |
1
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 < 𝑁 ↔ (𝑀 + 1) ≤ 𝑁)) |