| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | df-txp 35856 | . . 3
⊢ (𝐴 ⊗ 𝐵) = ((◡(1st ↾ (V × V))
∘ 𝐴) ∩ (◡(2nd ↾ (V × V))
∘ 𝐵)) | 
| 2 | 1 | breqi 5148 | . 2
⊢ (𝑋(𝐴 ⊗ 𝐵)〈𝑌, 𝑍〉 ↔ 𝑋((◡(1st ↾ (V × V))
∘ 𝐴) ∩ (◡(2nd ↾ (V × V))
∘ 𝐵))〈𝑌, 𝑍〉) | 
| 3 |  | brin 5194 | . 2
⊢ (𝑋((◡(1st ↾ (V × V))
∘ 𝐴) ∩ (◡(2nd ↾ (V × V))
∘ 𝐵))〈𝑌, 𝑍〉 ↔ (𝑋(◡(1st ↾ (V × V))
∘ 𝐴)〈𝑌, 𝑍〉 ∧ 𝑋(◡(2nd ↾ (V × V))
∘ 𝐵)〈𝑌, 𝑍〉)) | 
| 4 |  | brtxp.1 | . . . . 5
⊢ 𝑋 ∈ V | 
| 5 |  | opex 5468 | . . . . 5
⊢
〈𝑌, 𝑍〉 ∈ V | 
| 6 | 4, 5 | brco 5880 | . . . 4
⊢ (𝑋(◡(1st ↾ (V × V))
∘ 𝐴)〈𝑌, 𝑍〉 ↔ ∃𝑦(𝑋𝐴𝑦 ∧ 𝑦◡(1st ↾ (V ×
V))〈𝑌, 𝑍〉)) | 
| 7 |  | vex 3483 | . . . . . . . 8
⊢ 𝑦 ∈ V | 
| 8 | 7, 5 | brcnv 5892 | . . . . . . 7
⊢ (𝑦◡(1st ↾ (V ×
V))〈𝑌, 𝑍〉 ↔ 〈𝑌, 𝑍〉(1st ↾ (V ×
V))𝑦) | 
| 9 |  | brtxp.2 | . . . . . . . . 9
⊢ 𝑌 ∈ V | 
| 10 |  | brtxp.3 | . . . . . . . . 9
⊢ 𝑍 ∈ V | 
| 11 | 9, 10 | opelvv 5724 | . . . . . . . 8
⊢
〈𝑌, 𝑍〉 ∈ (V ×
V) | 
| 12 | 7 | brresi 6005 | . . . . . . . 8
⊢
(〈𝑌, 𝑍〉(1st ↾ (V
× V))𝑦 ↔
(〈𝑌, 𝑍〉 ∈ (V × V) ∧
〈𝑌, 𝑍〉1st 𝑦)) | 
| 13 | 11, 12 | mpbiran 709 | . . . . . . 7
⊢
(〈𝑌, 𝑍〉(1st ↾ (V
× V))𝑦 ↔
〈𝑌, 𝑍〉1st 𝑦) | 
| 14 | 9, 10 | br1steq 35772 | . . . . . . 7
⊢
(〈𝑌, 𝑍〉1st 𝑦 ↔ 𝑦 = 𝑌) | 
| 15 | 8, 13, 14 | 3bitri 297 | . . . . . 6
⊢ (𝑦◡(1st ↾ (V ×
V))〈𝑌, 𝑍〉 ↔ 𝑦 = 𝑌) | 
| 16 | 15 | anbi1ci 626 | . . . . 5
⊢ ((𝑋𝐴𝑦 ∧ 𝑦◡(1st ↾ (V ×
V))〈𝑌, 𝑍〉) ↔ (𝑦 = 𝑌 ∧ 𝑋𝐴𝑦)) | 
| 17 | 16 | exbii 1847 | . . . 4
⊢
(∃𝑦(𝑋𝐴𝑦 ∧ 𝑦◡(1st ↾ (V ×
V))〈𝑌, 𝑍〉) ↔ ∃𝑦(𝑦 = 𝑌 ∧ 𝑋𝐴𝑦)) | 
| 18 |  | breq2 5146 | . . . . 5
⊢ (𝑦 = 𝑌 → (𝑋𝐴𝑦 ↔ 𝑋𝐴𝑌)) | 
| 19 | 9, 18 | ceqsexv 3531 | . . . 4
⊢
(∃𝑦(𝑦 = 𝑌 ∧ 𝑋𝐴𝑦) ↔ 𝑋𝐴𝑌) | 
| 20 | 6, 17, 19 | 3bitri 297 | . . 3
⊢ (𝑋(◡(1st ↾ (V × V))
∘ 𝐴)〈𝑌, 𝑍〉 ↔ 𝑋𝐴𝑌) | 
| 21 | 4, 5 | brco 5880 | . . . 4
⊢ (𝑋(◡(2nd ↾ (V × V))
∘ 𝐵)〈𝑌, 𝑍〉 ↔ ∃𝑧(𝑋𝐵𝑧 ∧ 𝑧◡(2nd ↾ (V ×
V))〈𝑌, 𝑍〉)) | 
| 22 |  | vex 3483 | . . . . . . . 8
⊢ 𝑧 ∈ V | 
| 23 | 22, 5 | brcnv 5892 | . . . . . . 7
⊢ (𝑧◡(2nd ↾ (V ×
V))〈𝑌, 𝑍〉 ↔ 〈𝑌, 𝑍〉(2nd ↾ (V ×
V))𝑧) | 
| 24 | 22 | brresi 6005 | . . . . . . . 8
⊢
(〈𝑌, 𝑍〉(2nd ↾ (V
× V))𝑧 ↔
(〈𝑌, 𝑍〉 ∈ (V × V) ∧
〈𝑌, 𝑍〉2nd 𝑧)) | 
| 25 | 11, 24 | mpbiran 709 | . . . . . . 7
⊢
(〈𝑌, 𝑍〉(2nd ↾ (V
× V))𝑧 ↔
〈𝑌, 𝑍〉2nd 𝑧) | 
| 26 | 9, 10 | br2ndeq 35773 | . . . . . . 7
⊢
(〈𝑌, 𝑍〉2nd 𝑧 ↔ 𝑧 = 𝑍) | 
| 27 | 23, 25, 26 | 3bitri 297 | . . . . . 6
⊢ (𝑧◡(2nd ↾ (V ×
V))〈𝑌, 𝑍〉 ↔ 𝑧 = 𝑍) | 
| 28 | 27 | anbi1ci 626 | . . . . 5
⊢ ((𝑋𝐵𝑧 ∧ 𝑧◡(2nd ↾ (V ×
V))〈𝑌, 𝑍〉) ↔ (𝑧 = 𝑍 ∧ 𝑋𝐵𝑧)) | 
| 29 | 28 | exbii 1847 | . . . 4
⊢
(∃𝑧(𝑋𝐵𝑧 ∧ 𝑧◡(2nd ↾ (V ×
V))〈𝑌, 𝑍〉) ↔ ∃𝑧(𝑧 = 𝑍 ∧ 𝑋𝐵𝑧)) | 
| 30 |  | breq2 5146 | . . . . 5
⊢ (𝑧 = 𝑍 → (𝑋𝐵𝑧 ↔ 𝑋𝐵𝑍)) | 
| 31 | 10, 30 | ceqsexv 3531 | . . . 4
⊢
(∃𝑧(𝑧 = 𝑍 ∧ 𝑋𝐵𝑧) ↔ 𝑋𝐵𝑍) | 
| 32 | 21, 29, 31 | 3bitri 297 | . . 3
⊢ (𝑋(◡(2nd ↾ (V × V))
∘ 𝐵)〈𝑌, 𝑍〉 ↔ 𝑋𝐵𝑍) | 
| 33 | 20, 32 | anbi12i 628 | . 2
⊢ ((𝑋(◡(1st ↾ (V × V))
∘ 𝐴)〈𝑌, 𝑍〉 ∧ 𝑋(◡(2nd ↾ (V × V))
∘ 𝐵)〈𝑌, 𝑍〉) ↔ (𝑋𝐴𝑌 ∧ 𝑋𝐵𝑍)) | 
| 34 | 2, 3, 33 | 3bitri 297 | 1
⊢ (𝑋(𝐴 ⊗ 𝐵)〈𝑌, 𝑍〉 ↔ (𝑋𝐴𝑌 ∧ 𝑋𝐵𝑍)) |