Proof of Theorem chebbnd1lem2
| Step | Hyp | Ref
| Expression |
| 1 | | 2rp 13040 |
. . . . 5
⊢ 2 ∈
ℝ+ |
| 2 | | 4nn 12350 |
. . . . . . 7
⊢ 4 ∈
ℕ |
| 3 | | 4z 12653 |
. . . . . . . . 9
⊢ 4 ∈
ℤ |
| 4 | 3 | a1i 11 |
. . . . . . . 8
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 4 ∈
ℤ) |
| 5 | | chebbnd1lem2.1 |
. . . . . . . . 9
⊢ 𝑀 = (⌊‘(𝑁 / 2)) |
| 6 | | rehalfcl 12495 |
. . . . . . . . . . 11
⊢ (𝑁 ∈ ℝ → (𝑁 / 2) ∈
ℝ) |
| 7 | 6 | adantr 480 |
. . . . . . . . . 10
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (𝑁 / 2) ∈
ℝ) |
| 8 | 7 | flcld 13839 |
. . . . . . . . 9
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) →
(⌊‘(𝑁 / 2))
∈ ℤ) |
| 9 | 5, 8 | eqeltrid 2844 |
. . . . . . . 8
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 𝑀 ∈ ℤ) |
| 10 | | 4t2e8 12435 |
. . . . . . . . . . . 12
⊢ (4
· 2) = 8 |
| 11 | | simpr 484 |
. . . . . . . . . . . 12
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 8 ≤ 𝑁) |
| 12 | 10, 11 | eqbrtrid 5177 |
. . . . . . . . . . 11
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (4 · 2)
≤ 𝑁) |
| 13 | | 4re 12351 |
. . . . . . . . . . . . 13
⊢ 4 ∈
ℝ |
| 14 | 13 | a1i 11 |
. . . . . . . . . . . 12
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 4 ∈
ℝ) |
| 15 | | simpl 482 |
. . . . . . . . . . . 12
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 𝑁 ∈ ℝ) |
| 16 | | 2re 12341 |
. . . . . . . . . . . . 13
⊢ 2 ∈
ℝ |
| 17 | 16 | a1i 11 |
. . . . . . . . . . . 12
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 2 ∈
ℝ) |
| 18 | | 2pos 12370 |
. . . . . . . . . . . . 13
⊢ 0 <
2 |
| 19 | 18 | a1i 11 |
. . . . . . . . . . . 12
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 0 <
2) |
| 20 | | lemuldiv 12149 |
. . . . . . . . . . . 12
⊢ ((4
∈ ℝ ∧ 𝑁
∈ ℝ ∧ (2 ∈ ℝ ∧ 0 < 2)) → ((4 · 2)
≤ 𝑁 ↔ 4 ≤ (𝑁 / 2))) |
| 21 | 14, 15, 17, 19, 20 | syl112anc 1375 |
. . . . . . . . . . 11
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → ((4 · 2)
≤ 𝑁 ↔ 4 ≤ (𝑁 / 2))) |
| 22 | 12, 21 | mpbid 232 |
. . . . . . . . . 10
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 4 ≤ (𝑁 / 2)) |
| 23 | | flge 13846 |
. . . . . . . . . . 11
⊢ (((𝑁 / 2) ∈ ℝ ∧ 4
∈ ℤ) → (4 ≤ (𝑁 / 2) ↔ 4 ≤ (⌊‘(𝑁 / 2)))) |
| 24 | 7, 3, 23 | sylancl 586 |
. . . . . . . . . 10
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (4 ≤ (𝑁 / 2) ↔ 4 ≤
(⌊‘(𝑁 /
2)))) |
| 25 | 22, 24 | mpbid 232 |
. . . . . . . . 9
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 4 ≤
(⌊‘(𝑁 /
2))) |
| 26 | 25, 5 | breqtrrdi 5184 |
. . . . . . . 8
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 4 ≤ 𝑀) |
| 27 | | eluz2 12885 |
. . . . . . . 8
⊢ (𝑀 ∈
(ℤ≥‘4) ↔ (4 ∈ ℤ ∧ 𝑀 ∈ ℤ ∧ 4 ≤
𝑀)) |
| 28 | 4, 9, 26, 27 | syl3anbrc 1343 |
. . . . . . 7
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 𝑀 ∈
(ℤ≥‘4)) |
| 29 | | eluznn 12961 |
. . . . . . 7
⊢ ((4
∈ ℕ ∧ 𝑀
∈ (ℤ≥‘4)) → 𝑀 ∈ ℕ) |
| 30 | 2, 28, 29 | sylancr 587 |
. . . . . 6
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 𝑀 ∈ ℕ) |
| 31 | 30 | nnrpd 13076 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 𝑀 ∈
ℝ+) |
| 32 | | rpmulcl 13059 |
. . . . 5
⊢ ((2
∈ ℝ+ ∧ 𝑀 ∈ ℝ+) → (2
· 𝑀) ∈
ℝ+) |
| 33 | 1, 31, 32 | sylancr 587 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (2 · 𝑀) ∈
ℝ+) |
| 34 | 33 | relogcld 26666 |
. . 3
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (log‘(2
· 𝑀)) ∈
ℝ) |
| 35 | 34, 33 | rerpdivcld 13109 |
. 2
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → ((log‘(2
· 𝑀)) / (2 ·
𝑀)) ∈
ℝ) |
| 36 | | 0red 11265 |
. . . . . . 7
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 0 ∈
ℝ) |
| 37 | | 8re 12363 |
. . . . . . . 8
⊢ 8 ∈
ℝ |
| 38 | 37 | a1i 11 |
. . . . . . 7
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 8 ∈
ℝ) |
| 39 | | 8pos 12379 |
. . . . . . . 8
⊢ 0 <
8 |
| 40 | 39 | a1i 11 |
. . . . . . 7
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 0 <
8) |
| 41 | 36, 38, 15, 40, 11 | ltletrd 11422 |
. . . . . 6
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 0 < 𝑁) |
| 42 | 15, 41 | elrpd 13075 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 𝑁 ∈
ℝ+) |
| 43 | 42 | rphalfcld 13090 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (𝑁 / 2) ∈
ℝ+) |
| 44 | 43 | relogcld 26666 |
. . 3
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (log‘(𝑁 / 2)) ∈
ℝ) |
| 45 | 44, 43 | rerpdivcld 13109 |
. 2
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) →
((log‘(𝑁 / 2)) /
(𝑁 / 2)) ∈
ℝ) |
| 46 | 42 | relogcld 26666 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (log‘𝑁) ∈
ℝ) |
| 47 | 46, 42 | rerpdivcld 13109 |
. . 3
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → ((log‘𝑁) / 𝑁) ∈ ℝ) |
| 48 | | remulcl 11241 |
. . 3
⊢ ((2
∈ ℝ ∧ ((log‘𝑁) / 𝑁) ∈ ℝ) → (2 ·
((log‘𝑁) / 𝑁)) ∈
ℝ) |
| 49 | 16, 47, 48 | sylancr 587 |
. 2
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (2 ·
((log‘𝑁) / 𝑁)) ∈
ℝ) |
| 50 | 9 | zred 12724 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 𝑀 ∈ ℝ) |
| 51 | | peano2re 11435 |
. . . . 5
⊢ (𝑀 ∈ ℝ → (𝑀 + 1) ∈
ℝ) |
| 52 | 50, 51 | syl 17 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (𝑀 + 1) ∈
ℝ) |
| 53 | | remulcl 11241 |
. . . . 5
⊢ ((2
∈ ℝ ∧ 𝑀
∈ ℝ) → (2 · 𝑀) ∈ ℝ) |
| 54 | 16, 50, 53 | sylancr 587 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (2 · 𝑀) ∈
ℝ) |
| 55 | | flltp1 13841 |
. . . . . 6
⊢ ((𝑁 / 2) ∈ ℝ →
(𝑁 / 2) <
((⌊‘(𝑁 / 2)) +
1)) |
| 56 | 7, 55 | syl 17 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (𝑁 / 2) <
((⌊‘(𝑁 / 2)) +
1)) |
| 57 | 5 | oveq1i 7442 |
. . . . 5
⊢ (𝑀 + 1) = ((⌊‘(𝑁 / 2)) + 1) |
| 58 | 56, 57 | breqtrrdi 5184 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (𝑁 / 2) < (𝑀 + 1)) |
| 59 | | 1red 11263 |
. . . . . 6
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 1 ∈
ℝ) |
| 60 | 30 | nnge1d 12315 |
. . . . . 6
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 1 ≤ 𝑀) |
| 61 | 59, 50, 50, 60 | leadd2dd 11879 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (𝑀 + 1) ≤ (𝑀 + 𝑀)) |
| 62 | 50 | recnd 11290 |
. . . . . 6
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 𝑀 ∈ ℂ) |
| 63 | 62 | 2timesd 12511 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (2 · 𝑀) = (𝑀 + 𝑀)) |
| 64 | 61, 63 | breqtrrd 5170 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (𝑀 + 1) ≤ (2 · 𝑀)) |
| 65 | 7, 52, 54, 58, 64 | ltletrd 11422 |
. . 3
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (𝑁 / 2) < (2 · 𝑀)) |
| 66 | | ere 16126 |
. . . . . 6
⊢ e ∈
ℝ |
| 67 | 66 | a1i 11 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → e ∈
ℝ) |
| 68 | | egt2lt3 16243 |
. . . . . . . . 9
⊢ (2 < e
∧ e < 3) |
| 69 | 68 | simpri 485 |
. . . . . . . 8
⊢ e <
3 |
| 70 | | 3lt4 12441 |
. . . . . . . 8
⊢ 3 <
4 |
| 71 | | 3re 12347 |
. . . . . . . . 9
⊢ 3 ∈
ℝ |
| 72 | 66, 71, 13 | lttri 11388 |
. . . . . . . 8
⊢ ((e <
3 ∧ 3 < 4) → e < 4) |
| 73 | 69, 70, 72 | mp2an 692 |
. . . . . . 7
⊢ e <
4 |
| 74 | 73 | a1i 11 |
. . . . . 6
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → e <
4) |
| 75 | 67, 14, 7, 74, 22 | ltletrd 11422 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → e < (𝑁 / 2)) |
| 76 | 67, 7, 75 | ltled 11410 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → e ≤ (𝑁 / 2)) |
| 77 | 67, 7, 54, 75, 65 | lttrd 11423 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → e < (2
· 𝑀)) |
| 78 | 67, 54, 77 | ltled 11410 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → e ≤ (2
· 𝑀)) |
| 79 | | logdivlt 26664 |
. . . 4
⊢ ((((𝑁 / 2) ∈ ℝ ∧ e
≤ (𝑁 / 2)) ∧ ((2
· 𝑀) ∈ ℝ
∧ e ≤ (2 · 𝑀))) → ((𝑁 / 2) < (2 · 𝑀) ↔ ((log‘(2 · 𝑀)) / (2 · 𝑀)) < ((log‘(𝑁 / 2)) / (𝑁 / 2)))) |
| 80 | 7, 76, 54, 78, 79 | syl22anc 838 |
. . 3
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → ((𝑁 / 2) < (2 · 𝑀) ↔ ((log‘(2 ·
𝑀)) / (2 · 𝑀)) < ((log‘(𝑁 / 2)) / (𝑁 / 2)))) |
| 81 | 65, 80 | mpbid 232 |
. 2
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → ((log‘(2
· 𝑀)) / (2 ·
𝑀)) < ((log‘(𝑁 / 2)) / (𝑁 / 2))) |
| 82 | | rphalflt 13065 |
. . . . . 6
⊢ (𝑁 ∈ ℝ+
→ (𝑁 / 2) < 𝑁) |
| 83 | 42, 82 | syl 17 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (𝑁 / 2) < 𝑁) |
| 84 | | logltb 26643 |
. . . . . 6
⊢ (((𝑁 / 2) ∈ ℝ+
∧ 𝑁 ∈
ℝ+) → ((𝑁 / 2) < 𝑁 ↔ (log‘(𝑁 / 2)) < (log‘𝑁))) |
| 85 | 43, 42, 84 | syl2anc 584 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → ((𝑁 / 2) < 𝑁 ↔ (log‘(𝑁 / 2)) < (log‘𝑁))) |
| 86 | 83, 85 | mpbid 232 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (log‘(𝑁 / 2)) < (log‘𝑁)) |
| 87 | 44, 46, 43, 86 | ltdiv1dd 13135 |
. . 3
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) →
((log‘(𝑁 / 2)) /
(𝑁 / 2)) <
((log‘𝑁) / (𝑁 / 2))) |
| 88 | 46 | recnd 11290 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → (log‘𝑁) ∈
ℂ) |
| 89 | 15 | recnd 11290 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 𝑁 ∈ ℂ) |
| 90 | 17 | recnd 11290 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 2 ∈
ℂ) |
| 91 | 42 | rpne0d 13083 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 𝑁 ≠ 0) |
| 92 | | 2ne0 12371 |
. . . . . 6
⊢ 2 ≠
0 |
| 93 | 92 | a1i 11 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → 2 ≠
0) |
| 94 | 88, 89, 90, 91, 93 | divdiv2d 12076 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → ((log‘𝑁) / (𝑁 / 2)) = (((log‘𝑁) · 2) / 𝑁)) |
| 95 | 88, 90 | mulcomd 11283 |
. . . . 5
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → ((log‘𝑁) · 2) = (2 ·
(log‘𝑁))) |
| 96 | 95 | oveq1d 7447 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) →
(((log‘𝑁) · 2)
/ 𝑁) = ((2 ·
(log‘𝑁)) / 𝑁)) |
| 97 | 90, 88, 89, 91 | divassd 12079 |
. . . 4
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → ((2 ·
(log‘𝑁)) / 𝑁) = (2 ·
((log‘𝑁) / 𝑁))) |
| 98 | 94, 96, 97 | 3eqtrd 2780 |
. . 3
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → ((log‘𝑁) / (𝑁 / 2)) = (2 · ((log‘𝑁) / 𝑁))) |
| 99 | 87, 98 | breqtrd 5168 |
. 2
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) →
((log‘(𝑁 / 2)) /
(𝑁 / 2)) < (2 ·
((log‘𝑁) / 𝑁))) |
| 100 | 35, 45, 49, 81, 99 | lttrd 11423 |
1
⊢ ((𝑁 ∈ ℝ ∧ 8 ≤
𝑁) → ((log‘(2
· 𝑀)) / (2 ·
𝑀)) < (2 ·
((log‘𝑁) / 𝑁))) |