| Step | Hyp | Ref
 | Expression | 
| 1 |   | sin0pilem2 15018 | 
. 2
⊢
∃𝑞 ∈
(2(,)4)((sin‘𝑞) = 0
∧ ∀𝑥 ∈
(0(,)𝑞)0 <
(sin‘𝑥)) | 
| 2 |   | df-pi 11818 | 
. . . . . 6
⊢ π =
inf((ℝ+ ∩ (◡sin
“ {0})), ℝ, < ) | 
| 3 |   | lttri3 8106 | 
. . . . . . . 8
⊢ ((𝑓 ∈ ℝ ∧ 𝑔 ∈ ℝ) → (𝑓 = 𝑔 ↔ (¬ 𝑓 < 𝑔 ∧ ¬ 𝑔 < 𝑓))) | 
| 4 | 3 | adantl 277 | 
. . . . . . 7
⊢ (((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) ∧ (𝑓 ∈ ℝ ∧ 𝑔 ∈ ℝ)) → (𝑓 = 𝑔 ↔ (¬ 𝑓 < 𝑔 ∧ ¬ 𝑔 < 𝑓))) | 
| 5 |   | elioore 9987 | 
. . . . . . . 8
⊢ (𝑞 ∈ (2(,)4) → 𝑞 ∈
ℝ) | 
| 6 | 5 | adantr 276 | 
. . . . . . 7
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → 𝑞 ∈ ℝ) | 
| 7 |   | 0re 8026 | 
. . . . . . . . . . . 12
⊢ 0 ∈
ℝ | 
| 8 | 7 | a1i 9 | 
. . . . . . . . . . 11
⊢ (𝑞 ∈ (2(,)4) → 0 ∈
ℝ) | 
| 9 |   | 2re 9060 | 
. . . . . . . . . . . 12
⊢ 2 ∈
ℝ | 
| 10 | 9 | a1i 9 | 
. . . . . . . . . . 11
⊢ (𝑞 ∈ (2(,)4) → 2 ∈
ℝ) | 
| 11 |   | 2pos 9081 | 
. . . . . . . . . . . 12
⊢ 0 <
2 | 
| 12 | 11 | a1i 9 | 
. . . . . . . . . . 11
⊢ (𝑞 ∈ (2(,)4) → 0 <
2) | 
| 13 |   | eliooord 10003 | 
. . . . . . . . . . . 12
⊢ (𝑞 ∈ (2(,)4) → (2 <
𝑞 ∧ 𝑞 < 4)) | 
| 14 | 13 | simpld 112 | 
. . . . . . . . . . 11
⊢ (𝑞 ∈ (2(,)4) → 2 <
𝑞) | 
| 15 | 8, 10, 5, 12, 14 | lttrd 8152 | 
. . . . . . . . . 10
⊢ (𝑞 ∈ (2(,)4) → 0 <
𝑞) | 
| 16 | 5, 15 | elrpd 9768 | 
. . . . . . . . 9
⊢ (𝑞 ∈ (2(,)4) → 𝑞 ∈
ℝ+) | 
| 17 | 16 | adantr 276 | 
. . . . . . . 8
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → 𝑞 ∈ ℝ+) | 
| 18 |   | simprl 529 | 
. . . . . . . . . 10
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → (sin‘𝑞) = 0) | 
| 19 |   | sinf 11869 | 
. . . . . . . . . . . . 13
⊢
sin:ℂ⟶ℂ | 
| 20 |   | ffun 5410 | 
. . . . . . . . . . . . 13
⊢
(sin:ℂ⟶ℂ → Fun sin) | 
| 21 | 19, 20 | ax-mp 5 | 
. . . . . . . . . . . 12
⊢ Fun
sin | 
| 22 | 5 | recnd 8055 | 
. . . . . . . . . . . . 13
⊢ (𝑞 ∈ (2(,)4) → 𝑞 ∈
ℂ) | 
| 23 | 19 | fdmi 5415 | 
. . . . . . . . . . . . 13
⊢ dom sin =
ℂ | 
| 24 | 22, 23 | eleqtrrdi 2290 | 
. . . . . . . . . . . 12
⊢ (𝑞 ∈ (2(,)4) → 𝑞 ∈ dom
sin) | 
| 25 |   | funbrfvb 5603 | 
. . . . . . . . . . . 12
⊢ ((Fun sin
∧ 𝑞 ∈ dom sin)
→ ((sin‘𝑞) = 0
↔ 𝑞sin0)) | 
| 26 | 21, 24, 25 | sylancr 414 | 
. . . . . . . . . . 11
⊢ (𝑞 ∈ (2(,)4) →
((sin‘𝑞) = 0 ↔
𝑞sin0)) | 
| 27 | 26 | adantr 276 | 
. . . . . . . . . 10
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → ((sin‘𝑞) = 0 ↔ 𝑞sin0)) | 
| 28 | 18, 27 | mpbid 147 | 
. . . . . . . . 9
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → 𝑞sin0) | 
| 29 |   | 0nn0 9264 | 
. . . . . . . . . 10
⊢ 0 ∈
ℕ0 | 
| 30 |   | vex 2766 | 
. . . . . . . . . . 11
⊢ 𝑞 ∈ V | 
| 31 | 30 | eliniseg 5039 | 
. . . . . . . . . 10
⊢ (0 ∈
ℕ0 → (𝑞 ∈ (◡sin “ {0}) ↔ 𝑞sin0)) | 
| 32 | 29, 31 | ax-mp 5 | 
. . . . . . . . 9
⊢ (𝑞 ∈ (◡sin “ {0}) ↔ 𝑞sin0) | 
| 33 | 28, 32 | sylibr 134 | 
. . . . . . . 8
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → 𝑞 ∈ (◡sin “ {0})) | 
| 34 | 17, 33 | elind 3348 | 
. . . . . . 7
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → 𝑞 ∈ (ℝ+ ∩ (◡sin “ {0}))) | 
| 35 |   | fveq2 5558 | 
. . . . . . . . . 10
⊢ (𝑥 = 𝑡 → (sin‘𝑥) = (sin‘𝑡)) | 
| 36 | 35 | breq2d 4045 | 
. . . . . . . . 9
⊢ (𝑥 = 𝑡 → (0 < (sin‘𝑥) ↔ 0 < (sin‘𝑡))) | 
| 37 |   | simprr 531 | 
. . . . . . . . . 10
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → ∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥)) | 
| 38 | 37 | ad2antrr 488 | 
. . . . . . . . 9
⊢ ((((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) ∧ 𝑡 ∈ (ℝ+ ∩ (◡sin “ {0}))) ∧ 𝑡 < 𝑞) → ∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥)) | 
| 39 |   | elinel1 3349 | 
. . . . . . . . . . . 12
⊢ (𝑡 ∈ (ℝ+
∩ (◡sin “ {0})) → 𝑡 ∈
ℝ+) | 
| 40 | 39 | rpred 9771 | 
. . . . . . . . . . 11
⊢ (𝑡 ∈ (ℝ+
∩ (◡sin “ {0})) → 𝑡 ∈
ℝ) | 
| 41 | 40 | ad2antlr 489 | 
. . . . . . . . . 10
⊢ ((((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) ∧ 𝑡 ∈ (ℝ+ ∩ (◡sin “ {0}))) ∧ 𝑡 < 𝑞) → 𝑡 ∈ ℝ) | 
| 42 | 39 | rpgt0d 9774 | 
. . . . . . . . . . 11
⊢ (𝑡 ∈ (ℝ+
∩ (◡sin “ {0})) → 0 <
𝑡) | 
| 43 | 42 | ad2antlr 489 | 
. . . . . . . . . 10
⊢ ((((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) ∧ 𝑡 ∈ (ℝ+ ∩ (◡sin “ {0}))) ∧ 𝑡 < 𝑞) → 0 < 𝑡) | 
| 44 |   | simpr 110 | 
. . . . . . . . . 10
⊢ ((((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) ∧ 𝑡 ∈ (ℝ+ ∩ (◡sin “ {0}))) ∧ 𝑡 < 𝑞) → 𝑡 < 𝑞) | 
| 45 |   | 0xr 8073 | 
. . . . . . . . . . 11
⊢ 0 ∈
ℝ* | 
| 46 | 5 | rexrd 8076 | 
. . . . . . . . . . . 12
⊢ (𝑞 ∈ (2(,)4) → 𝑞 ∈
ℝ*) | 
| 47 | 46 | ad3antrrr 492 | 
. . . . . . . . . . 11
⊢ ((((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) ∧ 𝑡 ∈ (ℝ+ ∩ (◡sin “ {0}))) ∧ 𝑡 < 𝑞) → 𝑞 ∈ ℝ*) | 
| 48 |   | elioo2 9996 | 
. . . . . . . . . . 11
⊢ ((0
∈ ℝ* ∧ 𝑞 ∈ ℝ*) → (𝑡 ∈ (0(,)𝑞) ↔ (𝑡 ∈ ℝ ∧ 0 < 𝑡 ∧ 𝑡 < 𝑞))) | 
| 49 | 45, 47, 48 | sylancr 414 | 
. . . . . . . . . 10
⊢ ((((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) ∧ 𝑡 ∈ (ℝ+ ∩ (◡sin “ {0}))) ∧ 𝑡 < 𝑞) → (𝑡 ∈ (0(,)𝑞) ↔ (𝑡 ∈ ℝ ∧ 0 < 𝑡 ∧ 𝑡 < 𝑞))) | 
| 50 | 41, 43, 44, 49 | mpbir3and 1182 | 
. . . . . . . . 9
⊢ ((((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) ∧ 𝑡 ∈ (ℝ+ ∩ (◡sin “ {0}))) ∧ 𝑡 < 𝑞) → 𝑡 ∈ (0(,)𝑞)) | 
| 51 | 36, 38, 50 | rspcdva 2873 | 
. . . . . . . 8
⊢ ((((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) ∧ 𝑡 ∈ (ℝ+ ∩ (◡sin “ {0}))) ∧ 𝑡 < 𝑞) → 0 < (sin‘𝑡)) | 
| 52 |   | elinel2 3350 | 
. . . . . . . . . 10
⊢ (𝑡 ∈ (ℝ+
∩ (◡sin “ {0})) → 𝑡 ∈ (◡sin “ {0})) | 
| 53 | 7 | ltnri 8119 | 
. . . . . . . . . . 11
⊢  ¬ 0
< 0 | 
| 54 |   | vex 2766 | 
. . . . . . . . . . . . . . 15
⊢ 𝑡 ∈ V | 
| 55 | 54 | eliniseg 5039 | 
. . . . . . . . . . . . . 14
⊢ (0 ∈
ℕ0 → (𝑡 ∈ (◡sin “ {0}) ↔ 𝑡sin0)) | 
| 56 | 29, 55 | ax-mp 5 | 
. . . . . . . . . . . . 13
⊢ (𝑡 ∈ (◡sin “ {0}) ↔ 𝑡sin0) | 
| 57 |   | funbrfv 5599 | 
. . . . . . . . . . . . . 14
⊢ (Fun sin
→ (𝑡sin0 →
(sin‘𝑡) =
0)) | 
| 58 | 21, 57 | ax-mp 5 | 
. . . . . . . . . . . . 13
⊢ (𝑡sin0 → (sin‘𝑡) = 0) | 
| 59 | 56, 58 | sylbi 121 | 
. . . . . . . . . . . 12
⊢ (𝑡 ∈ (◡sin “ {0}) → (sin‘𝑡) = 0) | 
| 60 | 59 | breq2d 4045 | 
. . . . . . . . . . 11
⊢ (𝑡 ∈ (◡sin “ {0}) → (0 <
(sin‘𝑡) ↔ 0 <
0)) | 
| 61 | 53, 60 | mtbiri 676 | 
. . . . . . . . . 10
⊢ (𝑡 ∈ (◡sin “ {0}) → ¬ 0 <
(sin‘𝑡)) | 
| 62 | 52, 61 | syl 14 | 
. . . . . . . . 9
⊢ (𝑡 ∈ (ℝ+
∩ (◡sin “ {0})) → ¬
0 < (sin‘𝑡)) | 
| 63 | 62 | ad2antlr 489 | 
. . . . . . . 8
⊢ ((((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) ∧ 𝑡 ∈ (ℝ+ ∩ (◡sin “ {0}))) ∧ 𝑡 < 𝑞) → ¬ 0 < (sin‘𝑡)) | 
| 64 | 51, 63 | pm2.65da 662 | 
. . . . . . 7
⊢ (((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) ∧ 𝑡 ∈ (ℝ+ ∩ (◡sin “ {0}))) → ¬ 𝑡 < 𝑞) | 
| 65 | 4, 6, 34, 64 | infminti 7093 | 
. . . . . 6
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) →
inf((ℝ+ ∩ (◡sin
“ {0})), ℝ, < ) = 𝑞) | 
| 66 | 2, 65 | eqtrid 2241 | 
. . . . 5
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → π = 𝑞) | 
| 67 |   | simpl 109 | 
. . . . 5
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → 𝑞 ∈ (2(,)4)) | 
| 68 | 66, 67 | eqeltrd 2273 | 
. . . 4
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → π ∈
(2(,)4)) | 
| 69 | 66 | fveqeq2d 5566 | 
. . . . 5
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → ((sin‘π) = 0
↔ (sin‘𝑞) =
0)) | 
| 70 | 18, 69 | mpbird 167 | 
. . . 4
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → (sin‘π) =
0) | 
| 71 | 68, 70 | jca 306 | 
. . 3
⊢ ((𝑞 ∈ (2(,)4) ∧
((sin‘𝑞) = 0 ∧
∀𝑥 ∈ (0(,)𝑞)0 < (sin‘𝑥))) → (π ∈ (2(,)4)
∧ (sin‘π) = 0)) | 
| 72 | 71 | rexlimiva 2609 | 
. 2
⊢
(∃𝑞 ∈
(2(,)4)((sin‘𝑞) = 0
∧ ∀𝑥 ∈
(0(,)𝑞)0 <
(sin‘𝑥)) → (π
∈ (2(,)4) ∧ (sin‘π) = 0)) | 
| 73 | 1, 72 | ax-mp 5 | 
1
⊢ (π
∈ (2(,)4) ∧ (sin‘π) = 0) |