| Step | Hyp | Ref
| Expression |
| 1 | | 2re 11090 |
. . . . 5
⊢ 2 ∈
ℝ |
| 2 | 1 | a1i 11 |
. . . 4
⊢ (⊤
→ 2 ∈ ℝ) |
| 3 | | 4re 11097 |
. . . . 5
⊢ 4 ∈
ℝ |
| 4 | 3 | a1i 11 |
. . . 4
⊢ (⊤
→ 4 ∈ ℝ) |
| 5 | | 0re 10040 |
. . . . 5
⊢ 0 ∈
ℝ |
| 6 | 5 | a1i 11 |
. . . 4
⊢ (⊤
→ 0 ∈ ℝ) |
| 7 | | 2lt4 11198 |
. . . . 5
⊢ 2 <
4 |
| 8 | 7 | a1i 11 |
. . . 4
⊢ (⊤
→ 2 < 4) |
| 9 | | iccssre 12255 |
. . . . . . 7
⊢ ((2
∈ ℝ ∧ 4 ∈ ℝ) → (2[,]4) ⊆
ℝ) |
| 10 | 1, 3, 9 | mp2an 708 |
. . . . . 6
⊢ (2[,]4)
⊆ ℝ |
| 11 | | ax-resscn 9993 |
. . . . . 6
⊢ ℝ
⊆ ℂ |
| 12 | 10, 11 | sstri 3612 |
. . . . 5
⊢ (2[,]4)
⊆ ℂ |
| 13 | 12 | a1i 11 |
. . . 4
⊢ (⊤
→ (2[,]4) ⊆ ℂ) |
| 14 | | sincn 24198 |
. . . . 5
⊢ sin
∈ (ℂ–cn→ℂ) |
| 15 | 14 | a1i 11 |
. . . 4
⊢ (⊤
→ sin ∈ (ℂ–cn→ℂ)) |
| 16 | 10 | sseli 3599 |
. . . . . 6
⊢ (𝑦 ∈ (2[,]4) → 𝑦 ∈
ℝ) |
| 17 | 16 | resincld 14873 |
. . . . 5
⊢ (𝑦 ∈ (2[,]4) →
(sin‘𝑦) ∈
ℝ) |
| 18 | 17 | adantl 482 |
. . . 4
⊢
((⊤ ∧ 𝑦
∈ (2[,]4)) → (sin‘𝑦) ∈ ℝ) |
| 19 | | sin4lt0 14925 |
. . . . . 6
⊢
(sin‘4) < 0 |
| 20 | | sincos2sgn 14924 |
. . . . . . 7
⊢ (0 <
(sin‘2) ∧ (cos‘2) < 0) |
| 21 | 20 | simpli 474 |
. . . . . 6
⊢ 0 <
(sin‘2) |
| 22 | 19, 21 | pm3.2i 471 |
. . . . 5
⊢
((sin‘4) < 0 ∧ 0 < (sin‘2)) |
| 23 | 22 | a1i 11 |
. . . 4
⊢ (⊤
→ ((sin‘4) < 0 ∧ 0 < (sin‘2))) |
| 24 | 2, 4, 6, 8, 13, 15, 18, 23 | ivth2 23224 |
. . 3
⊢ (⊤
→ ∃𝑥 ∈
(2(,)4)(sin‘𝑥) =
0) |
| 25 | 24 | trud 1493 |
. 2
⊢
∃𝑥 ∈
(2(,)4)(sin‘𝑥) =
0 |
| 26 | | df-pi 14803 |
. . . . . . 7
⊢ π =
inf((ℝ+ ∩ (◡sin
“ {0})), ℝ, < ) |
| 27 | | elioore 12205 |
. . . . . . . . . . 11
⊢ (𝑥 ∈ (2(,)4) → 𝑥 ∈
ℝ) |
| 28 | 27 | adantr 481 |
. . . . . . . . . 10
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
𝑥 ∈
ℝ) |
| 29 | 5 | a1i 11 |
. . . . . . . . . . 11
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) → 0
∈ ℝ) |
| 30 | 1 | a1i 11 |
. . . . . . . . . . 11
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) → 2
∈ ℝ) |
| 31 | | 2pos 11112 |
. . . . . . . . . . . 12
⊢ 0 <
2 |
| 32 | 31 | a1i 11 |
. . . . . . . . . . 11
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) → 0
< 2) |
| 33 | | eliooord 12233 |
. . . . . . . . . . . . 13
⊢ (𝑥 ∈ (2(,)4) → (2 <
𝑥 ∧ 𝑥 < 4)) |
| 34 | 33 | simpld 475 |
. . . . . . . . . . . 12
⊢ (𝑥 ∈ (2(,)4) → 2 <
𝑥) |
| 35 | 34 | adantr 481 |
. . . . . . . . . . 11
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) → 2
< 𝑥) |
| 36 | 29, 30, 28, 32, 35 | lttrd 10198 |
. . . . . . . . . 10
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) → 0
< 𝑥) |
| 37 | 28, 36 | elrpd 11869 |
. . . . . . . . 9
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
𝑥 ∈
ℝ+) |
| 38 | | simpr 477 |
. . . . . . . . 9
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(sin‘𝑥) =
0) |
| 39 | | pilem1 24205 |
. . . . . . . . 9
⊢ (𝑥 ∈ (ℝ+
∩ (◡sin “ {0})) ↔ (𝑥 ∈ ℝ+
∧ (sin‘𝑥) =
0)) |
| 40 | 37, 38, 39 | sylanbrc 698 |
. . . . . . . 8
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
𝑥 ∈
(ℝ+ ∩ (◡sin
“ {0}))) |
| 41 | | inss1 3833 |
. . . . . . . . . 10
⊢
(ℝ+ ∩ (◡sin
“ {0})) ⊆ ℝ+ |
| 42 | | rpssre 11843 |
. . . . . . . . . 10
⊢
ℝ+ ⊆ ℝ |
| 43 | 41, 42 | sstri 3612 |
. . . . . . . . 9
⊢
(ℝ+ ∩ (◡sin
“ {0})) ⊆ ℝ |
| 44 | 41 | sseli 3599 |
. . . . . . . . . . . 12
⊢ (𝑧 ∈ (ℝ+
∩ (◡sin “ {0})) → 𝑧 ∈
ℝ+) |
| 45 | 44 | rpge0d 11876 |
. . . . . . . . . . 11
⊢ (𝑧 ∈ (ℝ+
∩ (◡sin “ {0})) → 0 ≤
𝑧) |
| 46 | 45 | rgen 2922 |
. . . . . . . . . 10
⊢
∀𝑧 ∈
(ℝ+ ∩ (◡sin
“ {0}))0 ≤ 𝑧 |
| 47 | | breq1 4656 |
. . . . . . . . . . . 12
⊢ (𝑦 = 0 → (𝑦 ≤ 𝑧 ↔ 0 ≤ 𝑧)) |
| 48 | 47 | ralbidv 2986 |
. . . . . . . . . . 11
⊢ (𝑦 = 0 → (∀𝑧 ∈ (ℝ+
∩ (◡sin “ {0}))𝑦 ≤ 𝑧 ↔ ∀𝑧 ∈ (ℝ+ ∩ (◡sin “ {0}))0 ≤ 𝑧)) |
| 49 | 48 | rspcev 3309 |
. . . . . . . . . 10
⊢ ((0
∈ ℝ ∧ ∀𝑧 ∈ (ℝ+ ∩ (◡sin “ {0}))0 ≤ 𝑧) → ∃𝑦 ∈ ℝ ∀𝑧 ∈ (ℝ+ ∩ (◡sin “ {0}))𝑦 ≤ 𝑧) |
| 50 | 5, 46, 49 | mp2an 708 |
. . . . . . . . 9
⊢
∃𝑦 ∈
ℝ ∀𝑧 ∈
(ℝ+ ∩ (◡sin
“ {0}))𝑦 ≤ 𝑧 |
| 51 | | infrelb 11008 |
. . . . . . . . 9
⊢
(((ℝ+ ∩ (◡sin “ {0})) ⊆ ℝ ∧
∃𝑦 ∈ ℝ
∀𝑧 ∈
(ℝ+ ∩ (◡sin
“ {0}))𝑦 ≤ 𝑧 ∧ 𝑥 ∈ (ℝ+ ∩ (◡sin “ {0}))) →
inf((ℝ+ ∩ (◡sin
“ {0})), ℝ, < ) ≤ 𝑥) |
| 52 | 43, 50, 51 | mp3an12 1414 |
. . . . . . . 8
⊢ (𝑥 ∈ (ℝ+
∩ (◡sin “ {0})) →
inf((ℝ+ ∩ (◡sin
“ {0})), ℝ, < ) ≤ 𝑥) |
| 53 | 40, 52 | syl 17 |
. . . . . . 7
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
inf((ℝ+ ∩ (◡sin
“ {0})), ℝ, < ) ≤ 𝑥) |
| 54 | 26, 53 | syl5eqbr 4688 |
. . . . . 6
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
π ≤ 𝑥) |
| 55 | | simplll 798 |
. . . . . . . . . . . . 13
⊢ ((((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) ∧ 𝑦 ∈ (ℝ+
∩ (◡sin “ {0}))) → 𝑥 ∈
(2(,)4)) |
| 56 | | simpr 477 |
. . . . . . . . . . . . . . 15
⊢ ((((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) ∧ 𝑦 ∈ (ℝ+
∩ (◡sin “ {0}))) → 𝑦 ∈ (ℝ+
∩ (◡sin “
{0}))) |
| 57 | | pilem1 24205 |
. . . . . . . . . . . . . . 15
⊢ (𝑦 ∈ (ℝ+
∩ (◡sin “ {0})) ↔ (𝑦 ∈ ℝ+
∧ (sin‘𝑦) =
0)) |
| 58 | 56, 57 | sylib 208 |
. . . . . . . . . . . . . 14
⊢ ((((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) ∧ 𝑦 ∈ (ℝ+
∩ (◡sin “ {0}))) →
(𝑦 ∈
ℝ+ ∧ (sin‘𝑦) = 0)) |
| 59 | 58 | simpld 475 |
. . . . . . . . . . . . 13
⊢ ((((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) ∧ 𝑦 ∈ (ℝ+
∩ (◡sin “ {0}))) → 𝑦 ∈
ℝ+) |
| 60 | | simpllr 799 |
. . . . . . . . . . . . 13
⊢ ((((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) ∧ 𝑦 ∈ (ℝ+
∩ (◡sin “ {0}))) →
(sin‘𝑥) =
0) |
| 61 | 58 | simprd 479 |
. . . . . . . . . . . . 13
⊢ ((((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) ∧ 𝑦 ∈ (ℝ+
∩ (◡sin “ {0}))) →
(sin‘𝑦) =
0) |
| 62 | | simplr 792 |
. . . . . . . . . . . . 13
⊢ ((((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) ∧ 𝑦 ∈ (ℝ+
∩ (◡sin “ {0}))) → π
< 𝑥) |
| 63 | 55, 59, 60, 61, 62 | pilem2 24206 |
. . . . . . . . . . . 12
⊢ ((((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) ∧ 𝑦 ∈ (ℝ+
∩ (◡sin “ {0}))) →
((π + 𝑥) / 2) ≤ 𝑦) |
| 64 | 63 | ralrimiva 2966 |
. . . . . . . . . . 11
⊢ (((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) →
∀𝑦 ∈
(ℝ+ ∩ (◡sin
“ {0}))((π + 𝑥) /
2) ≤ 𝑦) |
| 65 | 43 | a1i 11 |
. . . . . . . . . . . 12
⊢ (((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) →
(ℝ+ ∩ (◡sin
“ {0})) ⊆ ℝ) |
| 66 | | ne0i 3921 |
. . . . . . . . . . . . . 14
⊢ (𝑥 ∈ (ℝ+
∩ (◡sin “ {0})) →
(ℝ+ ∩ (◡sin
“ {0})) ≠ ∅) |
| 67 | 40, 66 | syl 17 |
. . . . . . . . . . . . 13
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(ℝ+ ∩ (◡sin
“ {0})) ≠ ∅) |
| 68 | 67 | adantr 481 |
. . . . . . . . . . . 12
⊢ (((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) →
(ℝ+ ∩ (◡sin
“ {0})) ≠ ∅) |
| 69 | 50 | a1i 11 |
. . . . . . . . . . . 12
⊢ (((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) →
∃𝑦 ∈ ℝ
∀𝑧 ∈
(ℝ+ ∩ (◡sin
“ {0}))𝑦 ≤ 𝑧) |
| 70 | | infrecl 11005 |
. . . . . . . . . . . . . . . . . 18
⊢
(((ℝ+ ∩ (◡sin “ {0})) ⊆ ℝ ∧
(ℝ+ ∩ (◡sin
“ {0})) ≠ ∅ ∧ ∃𝑦 ∈ ℝ ∀𝑧 ∈ (ℝ+ ∩ (◡sin “ {0}))𝑦 ≤ 𝑧) → inf((ℝ+ ∩
(◡sin “ {0})), ℝ, < )
∈ ℝ) |
| 71 | 43, 50, 70 | mp3an13 1415 |
. . . . . . . . . . . . . . . . 17
⊢
((ℝ+ ∩ (◡sin “ {0})) ≠ ∅ →
inf((ℝ+ ∩ (◡sin
“ {0})), ℝ, < ) ∈ ℝ) |
| 72 | 67, 71 | syl 17 |
. . . . . . . . . . . . . . . 16
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
inf((ℝ+ ∩ (◡sin
“ {0})), ℝ, < ) ∈ ℝ) |
| 73 | 26, 72 | syl5eqel 2705 |
. . . . . . . . . . . . . . 15
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
π ∈ ℝ) |
| 74 | 73, 28 | readdcld 10069 |
. . . . . . . . . . . . . 14
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(π + 𝑥) ∈
ℝ) |
| 75 | 74 | adantr 481 |
. . . . . . . . . . . . 13
⊢ (((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) → (π +
𝑥) ∈
ℝ) |
| 76 | 75 | rehalfcld 11279 |
. . . . . . . . . . . 12
⊢ (((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) → ((π
+ 𝑥) / 2) ∈
ℝ) |
| 77 | | infregelb 11007 |
. . . . . . . . . . . 12
⊢
((((ℝ+ ∩ (◡sin “ {0})) ⊆ ℝ ∧
(ℝ+ ∩ (◡sin
“ {0})) ≠ ∅ ∧ ∃𝑦 ∈ ℝ ∀𝑧 ∈ (ℝ+ ∩ (◡sin “ {0}))𝑦 ≤ 𝑧) ∧ ((π + 𝑥) / 2) ∈ ℝ) → (((π + 𝑥) / 2) ≤
inf((ℝ+ ∩ (◡sin
“ {0})), ℝ, < ) ↔ ∀𝑦 ∈ (ℝ+ ∩ (◡sin “ {0}))((π + 𝑥) / 2) ≤ 𝑦)) |
| 78 | 65, 68, 69, 76, 77 | syl31anc 1329 |
. . . . . . . . . . 11
⊢ (((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) → (((π
+ 𝑥) / 2) ≤
inf((ℝ+ ∩ (◡sin
“ {0})), ℝ, < ) ↔ ∀𝑦 ∈ (ℝ+ ∩ (◡sin “ {0}))((π + 𝑥) / 2) ≤ 𝑦)) |
| 79 | 64, 78 | mpbird 247 |
. . . . . . . . . 10
⊢ (((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) → ((π
+ 𝑥) / 2) ≤
inf((ℝ+ ∩ (◡sin
“ {0})), ℝ, < )) |
| 80 | 79, 26 | syl6breqr 4695 |
. . . . . . . . 9
⊢ (((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) ∧
π < 𝑥) → ((π
+ 𝑥) / 2) ≤
π) |
| 81 | 80 | ex 450 |
. . . . . . . 8
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(π < 𝑥 → ((π
+ 𝑥) / 2) ≤
π)) |
| 82 | 73, 28 | ltnled 10184 |
. . . . . . . 8
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(π < 𝑥 ↔ ¬
𝑥 ≤
π)) |
| 83 | 73 | recnd 10068 |
. . . . . . . . . . . 12
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
π ∈ ℂ) |
| 84 | 28 | recnd 10068 |
. . . . . . . . . . . 12
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
𝑥 ∈
ℂ) |
| 85 | 83, 84 | addcomd 10238 |
. . . . . . . . . . 11
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(π + 𝑥) = (𝑥 + π)) |
| 86 | 85 | oveq1d 6665 |
. . . . . . . . . 10
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
((π + 𝑥) / 2) = ((𝑥 + π) / 2)) |
| 87 | 86 | breq1d 4663 |
. . . . . . . . 9
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(((π + 𝑥) / 2) ≤ π
↔ ((𝑥 + π) / 2)
≤ π)) |
| 88 | | avgle2 11273 |
. . . . . . . . . 10
⊢ ((𝑥 ∈ ℝ ∧ π
∈ ℝ) → (𝑥
≤ π ↔ ((𝑥 +
π) / 2) ≤ π)) |
| 89 | 28, 73, 88 | syl2anc 693 |
. . . . . . . . 9
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(𝑥 ≤ π ↔ ((𝑥 + π) / 2) ≤
π)) |
| 90 | 87, 89 | bitr4d 271 |
. . . . . . . 8
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(((π + 𝑥) / 2) ≤ π
↔ 𝑥 ≤
π)) |
| 91 | 81, 82, 90 | 3imtr3d 282 |
. . . . . . 7
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(¬ 𝑥 ≤ π →
𝑥 ≤
π)) |
| 92 | 91 | pm2.18d 124 |
. . . . . 6
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
𝑥 ≤
π) |
| 93 | 73, 28 | letri3d 10179 |
. . . . . 6
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(π = 𝑥 ↔ (π ≤
𝑥 ∧ 𝑥 ≤ π))) |
| 94 | 54, 92, 93 | mpbir2and 957 |
. . . . 5
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
π = 𝑥) |
| 95 | | simpl 473 |
. . . . 5
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
𝑥 ∈
(2(,)4)) |
| 96 | 94, 95 | eqeltrd 2701 |
. . . 4
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
π ∈ (2(,)4)) |
| 97 | 94 | fveq2d 6195 |
. . . . 5
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(sin‘π) = (sin‘𝑥)) |
| 98 | 97, 38 | eqtrd 2656 |
. . . 4
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(sin‘π) = 0) |
| 99 | 96, 98 | jca 554 |
. . 3
⊢ ((𝑥 ∈ (2(,)4) ∧
(sin‘𝑥) = 0) →
(π ∈ (2(,)4) ∧ (sin‘π) = 0)) |
| 100 | 99 | rexlimiva 3028 |
. 2
⊢
(∃𝑥 ∈
(2(,)4)(sin‘𝑥) = 0
→ (π ∈ (2(,)4) ∧ (sin‘π) = 0)) |
| 101 | 25, 100 | ax-mp 5 |
1
⊢ (π
∈ (2(,)4) ∧ (sin‘π) = 0) |