Proof of Theorem unxpdomlem2
| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | unxpdomlem2.3 | . . 3
⊢ (𝜑 → ¬ 𝑠 = 𝑡) | 
| 2 | 1 | adantr 480 | . 2
⊢ ((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) → ¬ 𝑠 = 𝑡) | 
| 3 |  | elun1 4182 | . . . . . . . . . 10
⊢ (𝑧 ∈ 𝑎 → 𝑧 ∈ (𝑎 ∪ 𝑏)) | 
| 4 | 3 | ad2antrl 728 | . . . . . . . . 9
⊢ ((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) → 𝑧 ∈ (𝑎 ∪ 𝑏)) | 
| 5 |  | unxpdomlem1.1 | . . . . . . . . . 10
⊢ 𝐹 = (𝑥 ∈ (𝑎 ∪ 𝑏) ↦ 𝐺) | 
| 6 |  | unxpdomlem1.2 | . . . . . . . . . 10
⊢ 𝐺 = if(𝑥 ∈ 𝑎, 〈𝑥, if(𝑥 = 𝑚, 𝑡, 𝑠)〉, 〈if(𝑥 = 𝑡, 𝑛, 𝑚), 𝑥〉) | 
| 7 | 5, 6 | unxpdomlem1 9286 | . . . . . . . . 9
⊢ (𝑧 ∈ (𝑎 ∪ 𝑏) → (𝐹‘𝑧) = if(𝑧 ∈ 𝑎, 〈𝑧, if(𝑧 = 𝑚, 𝑡, 𝑠)〉, 〈if(𝑧 = 𝑡, 𝑛, 𝑚), 𝑧〉)) | 
| 8 | 4, 7 | syl 17 | . . . . . . . 8
⊢ ((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) → (𝐹‘𝑧) = if(𝑧 ∈ 𝑎, 〈𝑧, if(𝑧 = 𝑚, 𝑡, 𝑠)〉, 〈if(𝑧 = 𝑡, 𝑛, 𝑚), 𝑧〉)) | 
| 9 |  | iftrue 4531 | . . . . . . . . 9
⊢ (𝑧 ∈ 𝑎 → if(𝑧 ∈ 𝑎, 〈𝑧, if(𝑧 = 𝑚, 𝑡, 𝑠)〉, 〈if(𝑧 = 𝑡, 𝑛, 𝑚), 𝑧〉) = 〈𝑧, if(𝑧 = 𝑚, 𝑡, 𝑠)〉) | 
| 10 | 9 | ad2antrl 728 | . . . . . . . 8
⊢ ((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) → if(𝑧 ∈ 𝑎, 〈𝑧, if(𝑧 = 𝑚, 𝑡, 𝑠)〉, 〈if(𝑧 = 𝑡, 𝑛, 𝑚), 𝑧〉) = 〈𝑧, if(𝑧 = 𝑚, 𝑡, 𝑠)〉) | 
| 11 | 8, 10 | eqtrd 2777 | . . . . . . 7
⊢ ((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) → (𝐹‘𝑧) = 〈𝑧, if(𝑧 = 𝑚, 𝑡, 𝑠)〉) | 
| 12 |  | unxpdomlem2.1 | . . . . . . . . . 10
⊢ (𝜑 → 𝑤 ∈ (𝑎 ∪ 𝑏)) | 
| 13 | 12 | adantr 480 | . . . . . . . . 9
⊢ ((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) → 𝑤 ∈ (𝑎 ∪ 𝑏)) | 
| 14 | 5, 6 | unxpdomlem1 9286 | . . . . . . . . 9
⊢ (𝑤 ∈ (𝑎 ∪ 𝑏) → (𝐹‘𝑤) = if(𝑤 ∈ 𝑎, 〈𝑤, if(𝑤 = 𝑚, 𝑡, 𝑠)〉, 〈if(𝑤 = 𝑡, 𝑛, 𝑚), 𝑤〉)) | 
| 15 | 13, 14 | syl 17 | . . . . . . . 8
⊢ ((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) → (𝐹‘𝑤) = if(𝑤 ∈ 𝑎, 〈𝑤, if(𝑤 = 𝑚, 𝑡, 𝑠)〉, 〈if(𝑤 = 𝑡, 𝑛, 𝑚), 𝑤〉)) | 
| 16 |  | iffalse 4534 | . . . . . . . . 9
⊢ (¬
𝑤 ∈ 𝑎 → if(𝑤 ∈ 𝑎, 〈𝑤, if(𝑤 = 𝑚, 𝑡, 𝑠)〉, 〈if(𝑤 = 𝑡, 𝑛, 𝑚), 𝑤〉) = 〈if(𝑤 = 𝑡, 𝑛, 𝑚), 𝑤〉) | 
| 17 | 16 | ad2antll 729 | . . . . . . . 8
⊢ ((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) → if(𝑤 ∈ 𝑎, 〈𝑤, if(𝑤 = 𝑚, 𝑡, 𝑠)〉, 〈if(𝑤 = 𝑡, 𝑛, 𝑚), 𝑤〉) = 〈if(𝑤 = 𝑡, 𝑛, 𝑚), 𝑤〉) | 
| 18 | 15, 17 | eqtrd 2777 | . . . . . . 7
⊢ ((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) → (𝐹‘𝑤) = 〈if(𝑤 = 𝑡, 𝑛, 𝑚), 𝑤〉) | 
| 19 | 11, 18 | eqeq12d 2753 | . . . . . 6
⊢ ((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) → ((𝐹‘𝑧) = (𝐹‘𝑤) ↔ 〈𝑧, if(𝑧 = 𝑚, 𝑡, 𝑠)〉 = 〈if(𝑤 = 𝑡, 𝑛, 𝑚), 𝑤〉)) | 
| 20 | 19 | biimpa 476 | . . . . 5
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → 〈𝑧, if(𝑧 = 𝑚, 𝑡, 𝑠)〉 = 〈if(𝑤 = 𝑡, 𝑛, 𝑚), 𝑤〉) | 
| 21 |  | vex 3484 | . . . . . 6
⊢ 𝑧 ∈ V | 
| 22 |  | vex 3484 | . . . . . . 7
⊢ 𝑡 ∈ V | 
| 23 |  | vex 3484 | . . . . . . 7
⊢ 𝑠 ∈ V | 
| 24 | 22, 23 | ifex 4576 | . . . . . 6
⊢ if(𝑧 = 𝑚, 𝑡, 𝑠) ∈ V | 
| 25 | 21, 24 | opth 5481 | . . . . 5
⊢
(〈𝑧, if(𝑧 = 𝑚, 𝑡, 𝑠)〉 = 〈if(𝑤 = 𝑡, 𝑛, 𝑚), 𝑤〉 ↔ (𝑧 = if(𝑤 = 𝑡, 𝑛, 𝑚) ∧ if(𝑧 = 𝑚, 𝑡, 𝑠) = 𝑤)) | 
| 26 | 20, 25 | sylib 218 | . . . 4
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → (𝑧 = if(𝑤 = 𝑡, 𝑛, 𝑚) ∧ if(𝑧 = 𝑚, 𝑡, 𝑠) = 𝑤)) | 
| 27 | 26 | simprd 495 | . . 3
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → if(𝑧 = 𝑚, 𝑡, 𝑠) = 𝑤) | 
| 28 |  | iftrue 4531 | . . . . . . 7
⊢ (𝑧 = 𝑚 → if(𝑧 = 𝑚, 𝑡, 𝑠) = 𝑡) | 
| 29 | 27 | eqeq1d 2739 | . . . . . . 7
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → (if(𝑧 = 𝑚, 𝑡, 𝑠) = 𝑡 ↔ 𝑤 = 𝑡)) | 
| 30 | 28, 29 | imbitrid 244 | . . . . . 6
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → (𝑧 = 𝑚 → 𝑤 = 𝑡)) | 
| 31 |  | iftrue 4531 | . . . . . . 7
⊢ (𝑤 = 𝑡 → if(𝑤 = 𝑡, 𝑛, 𝑚) = 𝑛) | 
| 32 | 26 | simpld 494 | . . . . . . . 8
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → 𝑧 = if(𝑤 = 𝑡, 𝑛, 𝑚)) | 
| 33 | 32 | eqeq1d 2739 | . . . . . . 7
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → (𝑧 = 𝑛 ↔ if(𝑤 = 𝑡, 𝑛, 𝑚) = 𝑛)) | 
| 34 | 31, 33 | imbitrrid 246 | . . . . . 6
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → (𝑤 = 𝑡 → 𝑧 = 𝑛)) | 
| 35 | 30, 34 | syld 47 | . . . . 5
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → (𝑧 = 𝑚 → 𝑧 = 𝑛)) | 
| 36 |  | unxpdomlem2.2 | . . . . . . 7
⊢ (𝜑 → ¬ 𝑚 = 𝑛) | 
| 37 | 36 | ad2antrr 726 | . . . . . 6
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → ¬ 𝑚 = 𝑛) | 
| 38 |  | equequ1 2024 | . . . . . . 7
⊢ (𝑧 = 𝑚 → (𝑧 = 𝑛 ↔ 𝑚 = 𝑛)) | 
| 39 | 38 | notbid 318 | . . . . . 6
⊢ (𝑧 = 𝑚 → (¬ 𝑧 = 𝑛 ↔ ¬ 𝑚 = 𝑛)) | 
| 40 | 37, 39 | syl5ibrcom 247 | . . . . 5
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → (𝑧 = 𝑚 → ¬ 𝑧 = 𝑛)) | 
| 41 | 35, 40 | pm2.65d 196 | . . . 4
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → ¬ 𝑧 = 𝑚) | 
| 42 | 41 | iffalsed 4536 | . . 3
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → if(𝑧 = 𝑚, 𝑡, 𝑠) = 𝑠) | 
| 43 |  | iffalse 4534 | . . . . 5
⊢ (¬
𝑤 = 𝑡 → if(𝑤 = 𝑡, 𝑛, 𝑚) = 𝑚) | 
| 44 | 32 | eqeq1d 2739 | . . . . 5
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → (𝑧 = 𝑚 ↔ if(𝑤 = 𝑡, 𝑛, 𝑚) = 𝑚)) | 
| 45 | 43, 44 | imbitrrid 246 | . . . 4
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → (¬ 𝑤 = 𝑡 → 𝑧 = 𝑚)) | 
| 46 | 41, 45 | mt3d 148 | . . 3
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → 𝑤 = 𝑡) | 
| 47 | 27, 42, 46 | 3eqtr3d 2785 | . 2
⊢ (((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) ∧ (𝐹‘𝑧) = (𝐹‘𝑤)) → 𝑠 = 𝑡) | 
| 48 | 2, 47 | mtand 816 | 1
⊢ ((𝜑 ∧ (𝑧 ∈ 𝑎 ∧ ¬ 𝑤 ∈ 𝑎)) → ¬ (𝐹‘𝑧) = (𝐹‘𝑤)) |