Proof of Theorem xporderlem
| Step | Hyp | Ref
 | Expression | 
| 1 |   | df-br 4034 | 
. . 3
⊢
(〈𝑎, 𝑏〉𝑇〈𝑐, 𝑑〉 ↔ 〈〈𝑎, 𝑏〉, 〈𝑐, 𝑑〉〉 ∈ 𝑇) | 
| 2 |   | xporderlem.1 | 
. . . 4
⊢ 𝑇 = {〈𝑥, 𝑦〉 ∣ ((𝑥 ∈ (𝐴 × 𝐵) ∧ 𝑦 ∈ (𝐴 × 𝐵)) ∧ ((1st ‘𝑥)𝑅(1st ‘𝑦) ∨ ((1st ‘𝑥) = (1st ‘𝑦) ∧ (2nd
‘𝑥)𝑆(2nd ‘𝑦))))} | 
| 3 | 2 | eleq2i 2263 | 
. . 3
⊢
(〈〈𝑎,
𝑏〉, 〈𝑐, 𝑑〉〉 ∈ 𝑇 ↔ 〈〈𝑎, 𝑏〉, 〈𝑐, 𝑑〉〉 ∈ {〈𝑥, 𝑦〉 ∣ ((𝑥 ∈ (𝐴 × 𝐵) ∧ 𝑦 ∈ (𝐴 × 𝐵)) ∧ ((1st ‘𝑥)𝑅(1st ‘𝑦) ∨ ((1st ‘𝑥) = (1st ‘𝑦) ∧ (2nd
‘𝑥)𝑆(2nd ‘𝑦))))}) | 
| 4 | 1, 3 | bitri 184 | 
. 2
⊢
(〈𝑎, 𝑏〉𝑇〈𝑐, 𝑑〉 ↔ 〈〈𝑎, 𝑏〉, 〈𝑐, 𝑑〉〉 ∈ {〈𝑥, 𝑦〉 ∣ ((𝑥 ∈ (𝐴 × 𝐵) ∧ 𝑦 ∈ (𝐴 × 𝐵)) ∧ ((1st ‘𝑥)𝑅(1st ‘𝑦) ∨ ((1st ‘𝑥) = (1st ‘𝑦) ∧ (2nd
‘𝑥)𝑆(2nd ‘𝑦))))}) | 
| 5 |   | vex 2766 | 
. . . 4
⊢ 𝑎 ∈ V | 
| 6 |   | vex 2766 | 
. . . 4
⊢ 𝑏 ∈ V | 
| 7 | 5, 6 | opex 4262 | 
. . 3
⊢
〈𝑎, 𝑏〉 ∈ V | 
| 8 |   | vex 2766 | 
. . . 4
⊢ 𝑐 ∈ V | 
| 9 |   | vex 2766 | 
. . . 4
⊢ 𝑑 ∈ V | 
| 10 | 8, 9 | opex 4262 | 
. . 3
⊢
〈𝑐, 𝑑〉 ∈ V | 
| 11 |   | eleq1 2259 | 
. . . . . 6
⊢ (𝑥 = 〈𝑎, 𝑏〉 → (𝑥 ∈ (𝐴 × 𝐵) ↔ 〈𝑎, 𝑏〉 ∈ (𝐴 × 𝐵))) | 
| 12 |   | opelxp 4693 | 
. . . . . 6
⊢
(〈𝑎, 𝑏〉 ∈ (𝐴 × 𝐵) ↔ (𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵)) | 
| 13 | 11, 12 | bitrdi 196 | 
. . . . 5
⊢ (𝑥 = 〈𝑎, 𝑏〉 → (𝑥 ∈ (𝐴 × 𝐵) ↔ (𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵))) | 
| 14 | 13 | anbi1d 465 | 
. . . 4
⊢ (𝑥 = 〈𝑎, 𝑏〉 → ((𝑥 ∈ (𝐴 × 𝐵) ∧ 𝑦 ∈ (𝐴 × 𝐵)) ↔ ((𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵) ∧ 𝑦 ∈ (𝐴 × 𝐵)))) | 
| 15 | 5, 6 | op1std 6206 | 
. . . . . 6
⊢ (𝑥 = 〈𝑎, 𝑏〉 → (1st ‘𝑥) = 𝑎) | 
| 16 | 15 | breq1d 4043 | 
. . . . 5
⊢ (𝑥 = 〈𝑎, 𝑏〉 → ((1st ‘𝑥)𝑅(1st ‘𝑦) ↔ 𝑎𝑅(1st ‘𝑦))) | 
| 17 | 15 | eqeq1d 2205 | 
. . . . . 6
⊢ (𝑥 = 〈𝑎, 𝑏〉 → ((1st ‘𝑥) = (1st ‘𝑦) ↔ 𝑎 = (1st ‘𝑦))) | 
| 18 | 5, 6 | op2ndd 6207 | 
. . . . . . 7
⊢ (𝑥 = 〈𝑎, 𝑏〉 → (2nd ‘𝑥) = 𝑏) | 
| 19 | 18 | breq1d 4043 | 
. . . . . 6
⊢ (𝑥 = 〈𝑎, 𝑏〉 → ((2nd ‘𝑥)𝑆(2nd ‘𝑦) ↔ 𝑏𝑆(2nd ‘𝑦))) | 
| 20 | 17, 19 | anbi12d 473 | 
. . . . 5
⊢ (𝑥 = 〈𝑎, 𝑏〉 → (((1st ‘𝑥) = (1st ‘𝑦) ∧ (2nd
‘𝑥)𝑆(2nd ‘𝑦)) ↔ (𝑎 = (1st ‘𝑦) ∧ 𝑏𝑆(2nd ‘𝑦)))) | 
| 21 | 16, 20 | orbi12d 794 | 
. . . 4
⊢ (𝑥 = 〈𝑎, 𝑏〉 → (((1st ‘𝑥)𝑅(1st ‘𝑦) ∨ ((1st ‘𝑥) = (1st ‘𝑦) ∧ (2nd
‘𝑥)𝑆(2nd ‘𝑦))) ↔ (𝑎𝑅(1st ‘𝑦) ∨ (𝑎 = (1st ‘𝑦) ∧ 𝑏𝑆(2nd ‘𝑦))))) | 
| 22 | 14, 21 | anbi12d 473 | 
. . 3
⊢ (𝑥 = 〈𝑎, 𝑏〉 → (((𝑥 ∈ (𝐴 × 𝐵) ∧ 𝑦 ∈ (𝐴 × 𝐵)) ∧ ((1st ‘𝑥)𝑅(1st ‘𝑦) ∨ ((1st ‘𝑥) = (1st ‘𝑦) ∧ (2nd
‘𝑥)𝑆(2nd ‘𝑦)))) ↔ (((𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵) ∧ 𝑦 ∈ (𝐴 × 𝐵)) ∧ (𝑎𝑅(1st ‘𝑦) ∨ (𝑎 = (1st ‘𝑦) ∧ 𝑏𝑆(2nd ‘𝑦)))))) | 
| 23 |   | eleq1 2259 | 
. . . . . 6
⊢ (𝑦 = 〈𝑐, 𝑑〉 → (𝑦 ∈ (𝐴 × 𝐵) ↔ 〈𝑐, 𝑑〉 ∈ (𝐴 × 𝐵))) | 
| 24 |   | opelxp 4693 | 
. . . . . 6
⊢
(〈𝑐, 𝑑〉 ∈ (𝐴 × 𝐵) ↔ (𝑐 ∈ 𝐴 ∧ 𝑑 ∈ 𝐵)) | 
| 25 | 23, 24 | bitrdi 196 | 
. . . . 5
⊢ (𝑦 = 〈𝑐, 𝑑〉 → (𝑦 ∈ (𝐴 × 𝐵) ↔ (𝑐 ∈ 𝐴 ∧ 𝑑 ∈ 𝐵))) | 
| 26 | 25 | anbi2d 464 | 
. . . 4
⊢ (𝑦 = 〈𝑐, 𝑑〉 → (((𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵) ∧ 𝑦 ∈ (𝐴 × 𝐵)) ↔ ((𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵) ∧ (𝑐 ∈ 𝐴 ∧ 𝑑 ∈ 𝐵)))) | 
| 27 | 8, 9 | op1std 6206 | 
. . . . . 6
⊢ (𝑦 = 〈𝑐, 𝑑〉 → (1st ‘𝑦) = 𝑐) | 
| 28 | 27 | breq2d 4045 | 
. . . . 5
⊢ (𝑦 = 〈𝑐, 𝑑〉 → (𝑎𝑅(1st ‘𝑦) ↔ 𝑎𝑅𝑐)) | 
| 29 | 27 | eqeq2d 2208 | 
. . . . . 6
⊢ (𝑦 = 〈𝑐, 𝑑〉 → (𝑎 = (1st ‘𝑦) ↔ 𝑎 = 𝑐)) | 
| 30 | 8, 9 | op2ndd 6207 | 
. . . . . . 7
⊢ (𝑦 = 〈𝑐, 𝑑〉 → (2nd ‘𝑦) = 𝑑) | 
| 31 | 30 | breq2d 4045 | 
. . . . . 6
⊢ (𝑦 = 〈𝑐, 𝑑〉 → (𝑏𝑆(2nd ‘𝑦) ↔ 𝑏𝑆𝑑)) | 
| 32 | 29, 31 | anbi12d 473 | 
. . . . 5
⊢ (𝑦 = 〈𝑐, 𝑑〉 → ((𝑎 = (1st ‘𝑦) ∧ 𝑏𝑆(2nd ‘𝑦)) ↔ (𝑎 = 𝑐 ∧ 𝑏𝑆𝑑))) | 
| 33 | 28, 32 | orbi12d 794 | 
. . . 4
⊢ (𝑦 = 〈𝑐, 𝑑〉 → ((𝑎𝑅(1st ‘𝑦) ∨ (𝑎 = (1st ‘𝑦) ∧ 𝑏𝑆(2nd ‘𝑦))) ↔ (𝑎𝑅𝑐 ∨ (𝑎 = 𝑐 ∧ 𝑏𝑆𝑑)))) | 
| 34 | 26, 33 | anbi12d 473 | 
. . 3
⊢ (𝑦 = 〈𝑐, 𝑑〉 → ((((𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵) ∧ 𝑦 ∈ (𝐴 × 𝐵)) ∧ (𝑎𝑅(1st ‘𝑦) ∨ (𝑎 = (1st ‘𝑦) ∧ 𝑏𝑆(2nd ‘𝑦)))) ↔ (((𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵) ∧ (𝑐 ∈ 𝐴 ∧ 𝑑 ∈ 𝐵)) ∧ (𝑎𝑅𝑐 ∨ (𝑎 = 𝑐 ∧ 𝑏𝑆𝑑))))) | 
| 35 | 7, 10, 22, 34 | opelopab 4306 | 
. 2
⊢
(〈〈𝑎,
𝑏〉, 〈𝑐, 𝑑〉〉 ∈ {〈𝑥, 𝑦〉 ∣ ((𝑥 ∈ (𝐴 × 𝐵) ∧ 𝑦 ∈ (𝐴 × 𝐵)) ∧ ((1st ‘𝑥)𝑅(1st ‘𝑦) ∨ ((1st ‘𝑥) = (1st ‘𝑦) ∧ (2nd
‘𝑥)𝑆(2nd ‘𝑦))))} ↔ (((𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵) ∧ (𝑐 ∈ 𝐴 ∧ 𝑑 ∈ 𝐵)) ∧ (𝑎𝑅𝑐 ∨ (𝑎 = 𝑐 ∧ 𝑏𝑆𝑑)))) | 
| 36 |   | an4 586 | 
. . 3
⊢ (((𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵) ∧ (𝑐 ∈ 𝐴 ∧ 𝑑 ∈ 𝐵)) ↔ ((𝑎 ∈ 𝐴 ∧ 𝑐 ∈ 𝐴) ∧ (𝑏 ∈ 𝐵 ∧ 𝑑 ∈ 𝐵))) | 
| 37 | 36 | anbi1i 458 | 
. 2
⊢ ((((𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵) ∧ (𝑐 ∈ 𝐴 ∧ 𝑑 ∈ 𝐵)) ∧ (𝑎𝑅𝑐 ∨ (𝑎 = 𝑐 ∧ 𝑏𝑆𝑑))) ↔ (((𝑎 ∈ 𝐴 ∧ 𝑐 ∈ 𝐴) ∧ (𝑏 ∈ 𝐵 ∧ 𝑑 ∈ 𝐵)) ∧ (𝑎𝑅𝑐 ∨ (𝑎 = 𝑐 ∧ 𝑏𝑆𝑑)))) | 
| 38 | 4, 35, 37 | 3bitri 206 | 
1
⊢
(〈𝑎, 𝑏〉𝑇〈𝑐, 𝑑〉 ↔ (((𝑎 ∈ 𝐴 ∧ 𝑐 ∈ 𝐴) ∧ (𝑏 ∈ 𝐵 ∧ 𝑑 ∈ 𝐵)) ∧ (𝑎𝑅𝑐 ∨ (𝑎 = 𝑐 ∧ 𝑏𝑆𝑑)))) |