Proof of Theorem ruclem1
| Step | Hyp | Ref
| Expression |
| 1 | | ruc.2 |
. . . . . 6
⊢ (𝜑 → 𝐷 = (𝑥 ∈ (ℝ × ℝ), 𝑦 ∈ ℝ ↦
⦋(((1st ‘𝑥) + (2nd ‘𝑥)) / 2) / 𝑚⦌if(𝑚 < 𝑦, 〈(1st ‘𝑥), 𝑚〉, 〈((𝑚 + (2nd ‘𝑥)) / 2), (2nd ‘𝑥)〉))) |
| 2 | 1 | oveqd 7448 |
. . . . 5
⊢ (𝜑 → (〈𝐴, 𝐵〉𝐷𝑀) = (〈𝐴, 𝐵〉(𝑥 ∈ (ℝ × ℝ), 𝑦 ∈ ℝ ↦
⦋(((1st ‘𝑥) + (2nd ‘𝑥)) / 2) / 𝑚⦌if(𝑚 < 𝑦, 〈(1st ‘𝑥), 𝑚〉, 〈((𝑚 + (2nd ‘𝑥)) / 2), (2nd ‘𝑥)〉))𝑀)) |
| 3 | | ruclem1.3 |
. . . . . . 7
⊢ (𝜑 → 𝐴 ∈ ℝ) |
| 4 | | ruclem1.4 |
. . . . . . 7
⊢ (𝜑 → 𝐵 ∈ ℝ) |
| 5 | 3, 4 | opelxpd 5724 |
. . . . . 6
⊢ (𝜑 → 〈𝐴, 𝐵〉 ∈ (ℝ ×
ℝ)) |
| 6 | | ruclem1.5 |
. . . . . 6
⊢ (𝜑 → 𝑀 ∈ ℝ) |
| 7 | | simpr 484 |
. . . . . . . . . . 11
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → 𝑦 = 𝑀) |
| 8 | 7 | breq2d 5155 |
. . . . . . . . . 10
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → (𝑚 < 𝑦 ↔ 𝑚 < 𝑀)) |
| 9 | | simpl 482 |
. . . . . . . . . . . 12
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → 𝑥 = 〈𝐴, 𝐵〉) |
| 10 | 9 | fveq2d 6910 |
. . . . . . . . . . 11
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → (1st ‘𝑥) = (1st
‘〈𝐴, 𝐵〉)) |
| 11 | 10 | opeq1d 4879 |
. . . . . . . . . 10
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → 〈(1st ‘𝑥), 𝑚〉 = 〈(1st
‘〈𝐴, 𝐵〉), 𝑚〉) |
| 12 | 9 | fveq2d 6910 |
. . . . . . . . . . . . 13
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → (2nd ‘𝑥) = (2nd
‘〈𝐴, 𝐵〉)) |
| 13 | 12 | oveq2d 7447 |
. . . . . . . . . . . 12
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → (𝑚 + (2nd ‘𝑥)) = (𝑚 + (2nd ‘〈𝐴, 𝐵〉))) |
| 14 | 13 | oveq1d 7446 |
. . . . . . . . . . 11
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → ((𝑚 + (2nd ‘𝑥)) / 2) = ((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2)) |
| 15 | 14, 12 | opeq12d 4881 |
. . . . . . . . . 10
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → 〈((𝑚 + (2nd ‘𝑥)) / 2), (2nd ‘𝑥)〉 = 〈((𝑚 + (2nd
‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉) |
| 16 | 8, 11, 15 | ifbieq12d 4554 |
. . . . . . . . 9
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → if(𝑚 < 𝑦, 〈(1st ‘𝑥), 𝑚〉, 〈((𝑚 + (2nd ‘𝑥)) / 2), (2nd ‘𝑥)〉) = if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉)) |
| 17 | 16 | csbeq2dv 3906 |
. . . . . . . 8
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → ⦋(((1st
‘𝑥) + (2nd
‘𝑥)) / 2) / 𝑚⦌if(𝑚 < 𝑦, 〈(1st ‘𝑥), 𝑚〉, 〈((𝑚 + (2nd ‘𝑥)) / 2), (2nd ‘𝑥)〉) =
⦋(((1st ‘𝑥) + (2nd ‘𝑥)) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉)) |
| 18 | 10, 12 | oveq12d 7449 |
. . . . . . . . . 10
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → ((1st ‘𝑥) + (2nd ‘𝑥)) = ((1st
‘〈𝐴, 𝐵〉) + (2nd
‘〈𝐴, 𝐵〉))) |
| 19 | 18 | oveq1d 7446 |
. . . . . . . . 9
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → (((1st ‘𝑥) + (2nd ‘𝑥)) / 2) = (((1st
‘〈𝐴, 𝐵〉) + (2nd
‘〈𝐴, 𝐵〉)) / 2)) |
| 20 | 19 | csbeq1d 3903 |
. . . . . . . 8
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → ⦋(((1st
‘𝑥) + (2nd
‘𝑥)) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉) =
⦋(((1st ‘〈𝐴, 𝐵〉) + (2nd ‘〈𝐴, 𝐵〉)) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉)) |
| 21 | 17, 20 | eqtrd 2777 |
. . . . . . 7
⊢ ((𝑥 = 〈𝐴, 𝐵〉 ∧ 𝑦 = 𝑀) → ⦋(((1st
‘𝑥) + (2nd
‘𝑥)) / 2) / 𝑚⦌if(𝑚 < 𝑦, 〈(1st ‘𝑥), 𝑚〉, 〈((𝑚 + (2nd ‘𝑥)) / 2), (2nd ‘𝑥)〉) =
⦋(((1st ‘〈𝐴, 𝐵〉) + (2nd ‘〈𝐴, 𝐵〉)) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉)) |
| 22 | | eqid 2737 |
. . . . . . 7
⊢ (𝑥 ∈ (ℝ ×
ℝ), 𝑦 ∈ ℝ
↦ ⦋(((1st ‘𝑥) + (2nd ‘𝑥)) / 2) / 𝑚⦌if(𝑚 < 𝑦, 〈(1st ‘𝑥), 𝑚〉, 〈((𝑚 + (2nd ‘𝑥)) / 2), (2nd ‘𝑥)〉)) = (𝑥 ∈ (ℝ × ℝ), 𝑦 ∈ ℝ ↦
⦋(((1st ‘𝑥) + (2nd ‘𝑥)) / 2) / 𝑚⦌if(𝑚 < 𝑦, 〈(1st ‘𝑥), 𝑚〉, 〈((𝑚 + (2nd ‘𝑥)) / 2), (2nd ‘𝑥)〉)) |
| 23 | | opex 5469 |
. . . . . . . . 9
⊢
〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉 ∈ V |
| 24 | | opex 5469 |
. . . . . . . . 9
⊢
〈((𝑚 +
(2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉 ∈
V |
| 25 | 23, 24 | ifex 4576 |
. . . . . . . 8
⊢ if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉) ∈
V |
| 26 | 25 | csbex 5311 |
. . . . . . 7
⊢
⦋(((1st ‘〈𝐴, 𝐵〉) + (2nd ‘〈𝐴, 𝐵〉)) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉) ∈
V |
| 27 | 21, 22, 26 | ovmpoa 7588 |
. . . . . 6
⊢
((〈𝐴, 𝐵〉 ∈ (ℝ ×
ℝ) ∧ 𝑀 ∈
ℝ) → (〈𝐴,
𝐵〉(𝑥 ∈ (ℝ × ℝ), 𝑦 ∈ ℝ ↦
⦋(((1st ‘𝑥) + (2nd ‘𝑥)) / 2) / 𝑚⦌if(𝑚 < 𝑦, 〈(1st ‘𝑥), 𝑚〉, 〈((𝑚 + (2nd ‘𝑥)) / 2), (2nd ‘𝑥)〉))𝑀) = ⦋(((1st
‘〈𝐴, 𝐵〉) + (2nd
‘〈𝐴, 𝐵〉)) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉)) |
| 28 | 5, 6, 27 | syl2anc 584 |
. . . . 5
⊢ (𝜑 → (〈𝐴, 𝐵〉(𝑥 ∈ (ℝ × ℝ), 𝑦 ∈ ℝ ↦
⦋(((1st ‘𝑥) + (2nd ‘𝑥)) / 2) / 𝑚⦌if(𝑚 < 𝑦, 〈(1st ‘𝑥), 𝑚〉, 〈((𝑚 + (2nd ‘𝑥)) / 2), (2nd ‘𝑥)〉))𝑀) = ⦋(((1st
‘〈𝐴, 𝐵〉) + (2nd
‘〈𝐴, 𝐵〉)) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉)) |
| 29 | 2, 28 | eqtrd 2777 |
. . . 4
⊢ (𝜑 → (〈𝐴, 𝐵〉𝐷𝑀) = ⦋(((1st
‘〈𝐴, 𝐵〉) + (2nd
‘〈𝐴, 𝐵〉)) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉)) |
| 30 | | op1stg 8026 |
. . . . . . . . 9
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) →
(1st ‘〈𝐴, 𝐵〉) = 𝐴) |
| 31 | 3, 4, 30 | syl2anc 584 |
. . . . . . . 8
⊢ (𝜑 → (1st
‘〈𝐴, 𝐵〉) = 𝐴) |
| 32 | | op2ndg 8027 |
. . . . . . . . 9
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) →
(2nd ‘〈𝐴, 𝐵〉) = 𝐵) |
| 33 | 3, 4, 32 | syl2anc 584 |
. . . . . . . 8
⊢ (𝜑 → (2nd
‘〈𝐴, 𝐵〉) = 𝐵) |
| 34 | 31, 33 | oveq12d 7449 |
. . . . . . 7
⊢ (𝜑 → ((1st
‘〈𝐴, 𝐵〉) + (2nd
‘〈𝐴, 𝐵〉)) = (𝐴 + 𝐵)) |
| 35 | 34 | oveq1d 7446 |
. . . . . 6
⊢ (𝜑 → (((1st
‘〈𝐴, 𝐵〉) + (2nd
‘〈𝐴, 𝐵〉)) / 2) = ((𝐴 + 𝐵) / 2)) |
| 36 | 35 | csbeq1d 3903 |
. . . . 5
⊢ (𝜑 →
⦋(((1st ‘〈𝐴, 𝐵〉) + (2nd ‘〈𝐴, 𝐵〉)) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉) =
⦋((𝐴 + 𝐵) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉)) |
| 37 | | ovex 7464 |
. . . . . . 7
⊢ ((𝐴 + 𝐵) / 2) ∈ V |
| 38 | | breq1 5146 |
. . . . . . . 8
⊢ (𝑚 = ((𝐴 + 𝐵) / 2) → (𝑚 < 𝑀 ↔ ((𝐴 + 𝐵) / 2) < 𝑀)) |
| 39 | | opeq2 4874 |
. . . . . . . 8
⊢ (𝑚 = ((𝐴 + 𝐵) / 2) → 〈(1st
‘〈𝐴, 𝐵〉), 𝑚〉 = 〈(1st
‘〈𝐴, 𝐵〉), ((𝐴 + 𝐵) / 2)〉) |
| 40 | | oveq1 7438 |
. . . . . . . . . 10
⊢ (𝑚 = ((𝐴 + 𝐵) / 2) → (𝑚 + (2nd ‘〈𝐴, 𝐵〉)) = (((𝐴 + 𝐵) / 2) + (2nd ‘〈𝐴, 𝐵〉))) |
| 41 | 40 | oveq1d 7446 |
. . . . . . . . 9
⊢ (𝑚 = ((𝐴 + 𝐵) / 2) → ((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2) = ((((𝐴 + 𝐵) / 2) + (2nd ‘〈𝐴, 𝐵〉)) / 2)) |
| 42 | 41 | opeq1d 4879 |
. . . . . . . 8
⊢ (𝑚 = ((𝐴 + 𝐵) / 2) → 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉 = 〈((((𝐴 + 𝐵) / 2) + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉) |
| 43 | 38, 39, 42 | ifbieq12d 4554 |
. . . . . . 7
⊢ (𝑚 = ((𝐴 + 𝐵) / 2) → if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉) = if(((𝐴 + 𝐵) / 2) < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉)) |
| 44 | 37, 43 | csbie 3934 |
. . . . . 6
⊢
⦋((𝐴 +
𝐵) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉) = if(((𝐴 + 𝐵) / 2) < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉) |
| 45 | 31 | opeq1d 4879 |
. . . . . . 7
⊢ (𝜑 → 〈(1st
‘〈𝐴, 𝐵〉), ((𝐴 + 𝐵) / 2)〉 = 〈𝐴, ((𝐴 + 𝐵) / 2)〉) |
| 46 | 33 | oveq2d 7447 |
. . . . . . . . 9
⊢ (𝜑 → (((𝐴 + 𝐵) / 2) + (2nd ‘〈𝐴, 𝐵〉)) = (((𝐴 + 𝐵) / 2) + 𝐵)) |
| 47 | 46 | oveq1d 7446 |
. . . . . . . 8
⊢ (𝜑 → ((((𝐴 + 𝐵) / 2) + (2nd ‘〈𝐴, 𝐵〉)) / 2) = ((((𝐴 + 𝐵) / 2) + 𝐵) / 2)) |
| 48 | 47, 33 | opeq12d 4881 |
. . . . . . 7
⊢ (𝜑 → 〈((((𝐴 + 𝐵) / 2) + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉 = 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉) |
| 49 | 45, 48 | ifeq12d 4547 |
. . . . . 6
⊢ (𝜑 → if(((𝐴 + 𝐵) / 2) < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉) = if(((𝐴 + 𝐵) / 2) < 𝑀, 〈𝐴, ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉)) |
| 50 | 44, 49 | eqtrid 2789 |
. . . . 5
⊢ (𝜑 → ⦋((𝐴 + 𝐵) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉) = if(((𝐴 + 𝐵) / 2) < 𝑀, 〈𝐴, ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉)) |
| 51 | 36, 50 | eqtrd 2777 |
. . . 4
⊢ (𝜑 →
⦋(((1st ‘〈𝐴, 𝐵〉) + (2nd ‘〈𝐴, 𝐵〉)) / 2) / 𝑚⦌if(𝑚 < 𝑀, 〈(1st ‘〈𝐴, 𝐵〉), 𝑚〉, 〈((𝑚 + (2nd ‘〈𝐴, 𝐵〉)) / 2), (2nd
‘〈𝐴, 𝐵〉)〉) = if(((𝐴 + 𝐵) / 2) < 𝑀, 〈𝐴, ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉)) |
| 52 | 29, 51 | eqtrd 2777 |
. . 3
⊢ (𝜑 → (〈𝐴, 𝐵〉𝐷𝑀) = if(((𝐴 + 𝐵) / 2) < 𝑀, 〈𝐴, ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉)) |
| 53 | 3, 4 | readdcld 11290 |
. . . . . 6
⊢ (𝜑 → (𝐴 + 𝐵) ∈ ℝ) |
| 54 | 53 | rehalfcld 12513 |
. . . . 5
⊢ (𝜑 → ((𝐴 + 𝐵) / 2) ∈ ℝ) |
| 55 | 3, 54 | opelxpd 5724 |
. . . 4
⊢ (𝜑 → 〈𝐴, ((𝐴 + 𝐵) / 2)〉 ∈ (ℝ ×
ℝ)) |
| 56 | 54, 4 | readdcld 11290 |
. . . . . 6
⊢ (𝜑 → (((𝐴 + 𝐵) / 2) + 𝐵) ∈ ℝ) |
| 57 | 56 | rehalfcld 12513 |
. . . . 5
⊢ (𝜑 → ((((𝐴 + 𝐵) / 2) + 𝐵) / 2) ∈ ℝ) |
| 58 | 57, 4 | opelxpd 5724 |
. . . 4
⊢ (𝜑 → 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉 ∈ (ℝ ×
ℝ)) |
| 59 | 55, 58 | ifcld 4572 |
. . 3
⊢ (𝜑 → if(((𝐴 + 𝐵) / 2) < 𝑀, 〈𝐴, ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉) ∈ (ℝ ×
ℝ)) |
| 60 | 52, 59 | eqeltrd 2841 |
. 2
⊢ (𝜑 → (〈𝐴, 𝐵〉𝐷𝑀) ∈ (ℝ ×
ℝ)) |
| 61 | | ruclem1.6 |
. . 3
⊢ 𝑋 = (1st
‘(〈𝐴, 𝐵〉𝐷𝑀)) |
| 62 | 52 | fveq2d 6910 |
. . . 4
⊢ (𝜑 → (1st
‘(〈𝐴, 𝐵〉𝐷𝑀)) = (1st ‘if(((𝐴 + 𝐵) / 2) < 𝑀, 〈𝐴, ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉))) |
| 63 | | fvif 6922 |
. . . . 5
⊢
(1st ‘if(((𝐴 + 𝐵) / 2) < 𝑀, 〈𝐴, ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉)) = if(((𝐴 + 𝐵) / 2) < 𝑀, (1st ‘〈𝐴, ((𝐴 + 𝐵) / 2)〉), (1st
‘〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉)) |
| 64 | | op1stg 8026 |
. . . . . . 7
⊢ ((𝐴 ∈ ℝ ∧ ((𝐴 + 𝐵) / 2) ∈ V) → (1st
‘〈𝐴, ((𝐴 + 𝐵) / 2)〉) = 𝐴) |
| 65 | 3, 37, 64 | sylancl 586 |
. . . . . 6
⊢ (𝜑 → (1st
‘〈𝐴, ((𝐴 + 𝐵) / 2)〉) = 𝐴) |
| 66 | | ovex 7464 |
. . . . . . 7
⊢ ((((𝐴 + 𝐵) / 2) + 𝐵) / 2) ∈ V |
| 67 | | op1stg 8026 |
. . . . . . 7
⊢
((((((𝐴 + 𝐵) / 2) + 𝐵) / 2) ∈ V ∧ 𝐵 ∈ ℝ) → (1st
‘〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉) = ((((𝐴 + 𝐵) / 2) + 𝐵) / 2)) |
| 68 | 66, 4, 67 | sylancr 587 |
. . . . . 6
⊢ (𝜑 → (1st
‘〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉) = ((((𝐴 + 𝐵) / 2) + 𝐵) / 2)) |
| 69 | 65, 68 | ifeq12d 4547 |
. . . . 5
⊢ (𝜑 → if(((𝐴 + 𝐵) / 2) < 𝑀, (1st ‘〈𝐴, ((𝐴 + 𝐵) / 2)〉), (1st
‘〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉)) = if(((𝐴 + 𝐵) / 2) < 𝑀, 𝐴, ((((𝐴 + 𝐵) / 2) + 𝐵) / 2))) |
| 70 | 63, 69 | eqtrid 2789 |
. . . 4
⊢ (𝜑 → (1st
‘if(((𝐴 + 𝐵) / 2) < 𝑀, 〈𝐴, ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉)) = if(((𝐴 + 𝐵) / 2) < 𝑀, 𝐴, ((((𝐴 + 𝐵) / 2) + 𝐵) / 2))) |
| 71 | 62, 70 | eqtrd 2777 |
. . 3
⊢ (𝜑 → (1st
‘(〈𝐴, 𝐵〉𝐷𝑀)) = if(((𝐴 + 𝐵) / 2) < 𝑀, 𝐴, ((((𝐴 + 𝐵) / 2) + 𝐵) / 2))) |
| 72 | 61, 71 | eqtrid 2789 |
. 2
⊢ (𝜑 → 𝑋 = if(((𝐴 + 𝐵) / 2) < 𝑀, 𝐴, ((((𝐴 + 𝐵) / 2) + 𝐵) / 2))) |
| 73 | | ruclem1.7 |
. . 3
⊢ 𝑌 = (2nd
‘(〈𝐴, 𝐵〉𝐷𝑀)) |
| 74 | 52 | fveq2d 6910 |
. . . 4
⊢ (𝜑 → (2nd
‘(〈𝐴, 𝐵〉𝐷𝑀)) = (2nd ‘if(((𝐴 + 𝐵) / 2) < 𝑀, 〈𝐴, ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉))) |
| 75 | | fvif 6922 |
. . . . 5
⊢
(2nd ‘if(((𝐴 + 𝐵) / 2) < 𝑀, 〈𝐴, ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉)) = if(((𝐴 + 𝐵) / 2) < 𝑀, (2nd ‘〈𝐴, ((𝐴 + 𝐵) / 2)〉), (2nd
‘〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉)) |
| 76 | | op2ndg 8027 |
. . . . . . 7
⊢ ((𝐴 ∈ ℝ ∧ ((𝐴 + 𝐵) / 2) ∈ V) → (2nd
‘〈𝐴, ((𝐴 + 𝐵) / 2)〉) = ((𝐴 + 𝐵) / 2)) |
| 77 | 3, 37, 76 | sylancl 586 |
. . . . . 6
⊢ (𝜑 → (2nd
‘〈𝐴, ((𝐴 + 𝐵) / 2)〉) = ((𝐴 + 𝐵) / 2)) |
| 78 | | op2ndg 8027 |
. . . . . . 7
⊢
((((((𝐴 + 𝐵) / 2) + 𝐵) / 2) ∈ V ∧ 𝐵 ∈ ℝ) → (2nd
‘〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉) = 𝐵) |
| 79 | 66, 4, 78 | sylancr 587 |
. . . . . 6
⊢ (𝜑 → (2nd
‘〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉) = 𝐵) |
| 80 | 77, 79 | ifeq12d 4547 |
. . . . 5
⊢ (𝜑 → if(((𝐴 + 𝐵) / 2) < 𝑀, (2nd ‘〈𝐴, ((𝐴 + 𝐵) / 2)〉), (2nd
‘〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉)) = if(((𝐴 + 𝐵) / 2) < 𝑀, ((𝐴 + 𝐵) / 2), 𝐵)) |
| 81 | 75, 80 | eqtrid 2789 |
. . . 4
⊢ (𝜑 → (2nd
‘if(((𝐴 + 𝐵) / 2) < 𝑀, 〈𝐴, ((𝐴 + 𝐵) / 2)〉, 〈((((𝐴 + 𝐵) / 2) + 𝐵) / 2), 𝐵〉)) = if(((𝐴 + 𝐵) / 2) < 𝑀, ((𝐴 + 𝐵) / 2), 𝐵)) |
| 82 | 74, 81 | eqtrd 2777 |
. . 3
⊢ (𝜑 → (2nd
‘(〈𝐴, 𝐵〉𝐷𝑀)) = if(((𝐴 + 𝐵) / 2) < 𝑀, ((𝐴 + 𝐵) / 2), 𝐵)) |
| 83 | 73, 82 | eqtrid 2789 |
. 2
⊢ (𝜑 → 𝑌 = if(((𝐴 + 𝐵) / 2) < 𝑀, ((𝐴 + 𝐵) / 2), 𝐵)) |
| 84 | 60, 72, 83 | 3jca 1129 |
1
⊢ (𝜑 → ((〈𝐴, 𝐵〉𝐷𝑀) ∈ (ℝ × ℝ) ∧
𝑋 = if(((𝐴 + 𝐵) / 2) < 𝑀, 𝐴, ((((𝐴 + 𝐵) / 2) + 𝐵) / 2)) ∧ 𝑌 = if(((𝐴 + 𝐵) / 2) < 𝑀, ((𝐴 + 𝐵) / 2), 𝐵))) |