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Theorem csbxpgVD 39879
Description: Virtual deduction proof of csbxp 5404. The following User's Proof is a Virtual Deduction proof completed automatically by the tools program completeusersproof.cmd, which invokes Mel L. O'Cat's mmj2 and Norm Megill's Metamath Proof Assistant. csbxp 5404 is csbxpgVD 39879 without virtual deductions and was automatically derived from csbxpgVD 39879.
1:: (   𝐴𝑉   ▶   𝐴𝑉   )
2:1: (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑤𝐵 𝐴 / 𝑥𝑤𝐴 / 𝑥𝐵)   )
3:1: (   𝐴𝑉   ▶   𝐴 / 𝑥𝑤 = 𝑤   )
4:3: (   𝐴𝑉   ▶   (𝐴 / 𝑥𝑤𝐴 / 𝑥𝐵𝑤𝐴 / 𝑥𝐵)   )
5:2,4: (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑤𝐵𝑤 𝐴 / 𝑥𝐵)   )
6:1: (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑦𝐶 𝐴 / 𝑥𝑦𝐴 / 𝑥𝐶)   )
7:1: (   𝐴𝑉   ▶   𝐴 / 𝑥𝑦 = 𝑦   )
8:7: (   𝐴𝑉   ▶   (𝐴 / 𝑥𝑦𝐴 / 𝑥𝐶𝑦𝐴 / 𝑥𝐶)   )
9:6,8: (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑦𝐶𝑦 𝐴 / 𝑥𝐶)   )
10:5,9: (   𝐴𝑉   ▶   (([𝐴 / 𝑥]𝑤𝐵 [𝐴 / 𝑥]𝑦𝐶) ↔ (𝑤𝐴 / 𝑥𝐵 𝑦𝐴 / 𝑥𝐶))   )
11:1: (   𝐴𝑉   ▶   ([𝐴 / 𝑥](𝑤𝐵 𝑦𝐶) ↔ ([𝐴 / 𝑥]𝑤𝐵[𝐴 / 𝑥]𝑦𝐶))   )
12:10,11: (   𝐴𝑉   ▶   ([𝐴 / 𝑥](𝑤𝐵 𝑦𝐶) ↔ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))   )
13:1: (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑧 = ⟨𝑤   ,    𝑦⟩ ↔ 𝑧 = ⟨𝑤, 𝑦⟩)   )
14:12,13: (   𝐴𝑉   ▶   (([𝐴 / 𝑥]𝑧 = ⟨𝑤    ,   𝑦⟩ ∧ [𝐴 / 𝑥](𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦 ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
15:1: (   𝐴𝑉   ▶   ([𝐴 / 𝑥](𝑧 = ⟨𝑤    ,   𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦 [𝐴 / 𝑥](𝑤𝐵𝑦𝐶)))   )
16:14,15: (   𝐴𝑉   ▶   ([𝐴 / 𝑥](𝑧 = ⟨𝑤    ,   𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
17:16: (   𝐴𝑉   ▶   𝑦([𝐴 / 𝑥](𝑧 = 𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
18:17: (   𝐴𝑉   ▶   (∃𝑦[𝐴 / 𝑥](𝑧 = 𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
19:1: (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑦(𝑧 = 𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦[𝐴 / 𝑥](𝑧 = 𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)))   )
20:18,19: (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑦(𝑧 = 𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
21:20: (   𝐴𝑉   ▶   𝑤([𝐴 / 𝑥]𝑦( 𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦(𝑧 = 𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
22:21: (   𝐴𝑉   ▶   (∃𝑤[𝐴 / 𝑥]𝑦( 𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = 𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
23:1: (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑤𝑦( 𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤[𝐴 / 𝑥]𝑦 (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)))   )
24:22,23: (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑤𝑦( 𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = 𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
25:24: (   𝐴𝑉   ▶   𝑧([𝐴 / 𝑥]𝑤 𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = 𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
26:25: (   𝐴𝑉   ▶   {𝑧[𝐴 / 𝑥]𝑤 𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧 ∣ ∃𝑤𝑦( 𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}    )
27:1: (   𝐴𝑉   ▶   𝐴 / 𝑥{𝑧 ∣ ∃𝑤 𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧[𝐴 / 𝑥] 𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))}   )
28:26,27: (   𝐴𝑉   ▶   𝐴 / 𝑥{𝑧 ∣ ∃𝑤 𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧 ∣ ∃𝑤𝑦( 𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}    )
29:: {⟨𝑤   ,   𝑦⟩ ∣ (𝑤𝐵𝑦𝐶)} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))}
30:: (𝐵 × 𝐶) = {⟨𝑤   ,   𝑦⟩ ∣ (𝑤𝐵 𝑦𝐶)}
31:29,30: (𝐵 × 𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤 , 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))}
32:31: 𝑥(𝐵 × 𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = 𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))}
33:1,32: (   𝐴𝑉   ▶   𝐴 / 𝑥(𝐵 × 𝐶) = 𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵 𝑦𝐶))}   )
34:28,33: (   𝐴𝑉   ▶   𝐴 / 𝑥(𝐵 × 𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵 𝑦𝐴 / 𝑥𝐶))}   )
35:: {⟨𝑤   ,   𝑦⟩ ∣ (𝑤𝐴 / 𝑥𝐵 𝑦𝐴 / 𝑥𝐶)} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}
36:: (𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶) = { 𝑤, 𝑦⟩ ∣ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)}
37:35,36: (𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵 𝑦𝐴 / 𝑥𝐶))}
38:34,37: (   𝐴𝑉   ▶   𝐴 / 𝑥(𝐵 × 𝐶) = (𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶)   )
qed:38: (𝐴𝑉𝐴 / 𝑥(𝐵 × 𝐶) = ( 𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶))
(Contributed by Alan Sare, 10-Nov-2012.) (Proof modification is discouraged.) (New usage is discouraged.)
Assertion
Ref Expression
csbxpgVD (𝐴𝑉𝐴 / 𝑥(𝐵 × 𝐶) = (𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶))

Proof of Theorem csbxpgVD
Dummy variables 𝑤 𝑦 𝑧 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 idn1 39549 . . . . . . . . . . . . . . . . . . 19 (   𝐴𝑉   ▶   𝐴𝑉   )
2 sbcel12 4177 . . . . . . . . . . . . . . . . . . . 20 ([𝐴 / 𝑥]𝑤𝐵𝐴 / 𝑥𝑤𝐴 / 𝑥𝐵)
32a1i 11 . . . . . . . . . . . . . . . . . . 19 (𝐴𝑉 → ([𝐴 / 𝑥]𝑤𝐵𝐴 / 𝑥𝑤𝐴 / 𝑥𝐵))
41, 3e1a 39611 . . . . . . . . . . . . . . . . . 18 (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑤𝐵𝐴 / 𝑥𝑤𝐴 / 𝑥𝐵)   )
5 csbconstg 3740 . . . . . . . . . . . . . . . . . . . 20 (𝐴𝑉𝐴 / 𝑥𝑤 = 𝑤)
61, 5e1a 39611 . . . . . . . . . . . . . . . . . . 19 (   𝐴𝑉   ▶   𝐴 / 𝑥𝑤 = 𝑤   )
7 eleq1 2865 . . . . . . . . . . . . . . . . . . 19 (𝐴 / 𝑥𝑤 = 𝑤 → (𝐴 / 𝑥𝑤𝐴 / 𝑥𝐵𝑤𝐴 / 𝑥𝐵))
86, 7e1a 39611 . . . . . . . . . . . . . . . . . 18 (   𝐴𝑉   ▶   (𝐴 / 𝑥𝑤𝐴 / 𝑥𝐵𝑤𝐴 / 𝑥𝐵)   )
9 bibi1 343 . . . . . . . . . . . . . . . . . . 19 (([𝐴 / 𝑥]𝑤𝐵𝐴 / 𝑥𝑤𝐴 / 𝑥𝐵) → (([𝐴 / 𝑥]𝑤𝐵𝑤𝐴 / 𝑥𝐵) ↔ (𝐴 / 𝑥𝑤𝐴 / 𝑥𝐵𝑤𝐴 / 𝑥𝐵)))
109biimprd 240 . . . . . . . . . . . . . . . . . 18 (([𝐴 / 𝑥]𝑤𝐵𝐴 / 𝑥𝑤𝐴 / 𝑥𝐵) → ((𝐴 / 𝑥𝑤𝐴 / 𝑥𝐵𝑤𝐴 / 𝑥𝐵) → ([𝐴 / 𝑥]𝑤𝐵𝑤𝐴 / 𝑥𝐵)))
114, 8, 10e11 39672 . . . . . . . . . . . . . . . . 17 (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑤𝐵𝑤𝐴 / 𝑥𝐵)   )
12 sbcel12 4177 . . . . . . . . . . . . . . . . . . . 20 ([𝐴 / 𝑥]𝑦𝐶𝐴 / 𝑥𝑦𝐴 / 𝑥𝐶)
1312a1i 11 . . . . . . . . . . . . . . . . . . 19 (𝐴𝑉 → ([𝐴 / 𝑥]𝑦𝐶𝐴 / 𝑥𝑦𝐴 / 𝑥𝐶))
141, 13e1a 39611 . . . . . . . . . . . . . . . . . 18 (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑦𝐶𝐴 / 𝑥𝑦𝐴 / 𝑥𝐶)   )
15 csbconstg 3740 . . . . . . . . . . . . . . . . . . . 20 (𝐴𝑉𝐴 / 𝑥𝑦 = 𝑦)
161, 15e1a 39611 . . . . . . . . . . . . . . . . . . 19 (   𝐴𝑉   ▶   𝐴 / 𝑥𝑦 = 𝑦   )
17 eleq1 2865 . . . . . . . . . . . . . . . . . . 19 (𝐴 / 𝑥𝑦 = 𝑦 → (𝐴 / 𝑥𝑦𝐴 / 𝑥𝐶𝑦𝐴 / 𝑥𝐶))
1816, 17e1a 39611 . . . . . . . . . . . . . . . . . 18 (   𝐴𝑉   ▶   (𝐴 / 𝑥𝑦𝐴 / 𝑥𝐶𝑦𝐴 / 𝑥𝐶)   )
19 bibi1 343 . . . . . . . . . . . . . . . . . . 19 (([𝐴 / 𝑥]𝑦𝐶𝐴 / 𝑥𝑦𝐴 / 𝑥𝐶) → (([𝐴 / 𝑥]𝑦𝐶𝑦𝐴 / 𝑥𝐶) ↔ (𝐴 / 𝑥𝑦𝐴 / 𝑥𝐶𝑦𝐴 / 𝑥𝐶)))
2019biimprd 240 . . . . . . . . . . . . . . . . . 18 (([𝐴 / 𝑥]𝑦𝐶𝐴 / 𝑥𝑦𝐴 / 𝑥𝐶) → ((𝐴 / 𝑥𝑦𝐴 / 𝑥𝐶𝑦𝐴 / 𝑥𝐶) → ([𝐴 / 𝑥]𝑦𝐶𝑦𝐴 / 𝑥𝐶)))
2114, 18, 20e11 39672 . . . . . . . . . . . . . . . . 17 (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑦𝐶𝑦𝐴 / 𝑥𝐶)   )
22 pm4.38 629 . . . . . . . . . . . . . . . . . 18 ((([𝐴 / 𝑥]𝑤𝐵𝑤𝐴 / 𝑥𝐵) ∧ ([𝐴 / 𝑥]𝑦𝐶𝑦𝐴 / 𝑥𝐶)) → (([𝐴 / 𝑥]𝑤𝐵[𝐴 / 𝑥]𝑦𝐶) ↔ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))
2322ex 402 . . . . . . . . . . . . . . . . 17 (([𝐴 / 𝑥]𝑤𝐵𝑤𝐴 / 𝑥𝐵) → (([𝐴 / 𝑥]𝑦𝐶𝑦𝐴 / 𝑥𝐶) → (([𝐴 / 𝑥]𝑤𝐵[𝐴 / 𝑥]𝑦𝐶) ↔ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))))
2411, 21, 23e11 39672 . . . . . . . . . . . . . . . 16 (   𝐴𝑉   ▶   (([𝐴 / 𝑥]𝑤𝐵[𝐴 / 𝑥]𝑦𝐶) ↔ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))   )
25 sbcan 3675 . . . . . . . . . . . . . . . . . 18 ([𝐴 / 𝑥](𝑤𝐵𝑦𝐶) ↔ ([𝐴 / 𝑥]𝑤𝐵[𝐴 / 𝑥]𝑦𝐶))
2625a1i 11 . . . . . . . . . . . . . . . . 17 (𝐴𝑉 → ([𝐴 / 𝑥](𝑤𝐵𝑦𝐶) ↔ ([𝐴 / 𝑥]𝑤𝐵[𝐴 / 𝑥]𝑦𝐶)))
271, 26e1a 39611 . . . . . . . . . . . . . . . 16 (   𝐴𝑉   ▶   ([𝐴 / 𝑥](𝑤𝐵𝑦𝐶) ↔ ([𝐴 / 𝑥]𝑤𝐵[𝐴 / 𝑥]𝑦𝐶))   )
28 bibi1 343 . . . . . . . . . . . . . . . . 17 (([𝐴 / 𝑥](𝑤𝐵𝑦𝐶) ↔ ([𝐴 / 𝑥]𝑤𝐵[𝐴 / 𝑥]𝑦𝐶)) → (([𝐴 / 𝑥](𝑤𝐵𝑦𝐶) ↔ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)) ↔ (([𝐴 / 𝑥]𝑤𝐵[𝐴 / 𝑥]𝑦𝐶) ↔ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))))
2928biimprcd 242 . . . . . . . . . . . . . . . 16 ((([𝐴 / 𝑥]𝑤𝐵[𝐴 / 𝑥]𝑦𝐶) ↔ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)) → (([𝐴 / 𝑥](𝑤𝐵𝑦𝐶) ↔ ([𝐴 / 𝑥]𝑤𝐵[𝐴 / 𝑥]𝑦𝐶)) → ([𝐴 / 𝑥](𝑤𝐵𝑦𝐶) ↔ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))))
3024, 27, 29e11 39672 . . . . . . . . . . . . . . 15 (   𝐴𝑉   ▶   ([𝐴 / 𝑥](𝑤𝐵𝑦𝐶) ↔ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))   )
31 sbcg 3698 . . . . . . . . . . . . . . . 16 (𝐴𝑉 → ([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ↔ 𝑧 = ⟨𝑤, 𝑦⟩))
321, 31e1a 39611 . . . . . . . . . . . . . . 15 (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ↔ 𝑧 = ⟨𝑤, 𝑦⟩)   )
33 pm4.38 629 . . . . . . . . . . . . . . . 16 ((([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ↔ 𝑧 = ⟨𝑤, 𝑦⟩) ∧ ([𝐴 / 𝑥](𝑤𝐵𝑦𝐶) ↔ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))) → (([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ∧ [𝐴 / 𝑥](𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))))
3433expcom 403 . . . . . . . . . . . . . . 15 (([𝐴 / 𝑥](𝑤𝐵𝑦𝐶) ↔ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)) → (([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ↔ 𝑧 = ⟨𝑤, 𝑦⟩) → (([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ∧ [𝐴 / 𝑥](𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))))
3530, 32, 34e11 39672 . . . . . . . . . . . . . 14 (   𝐴𝑉   ▶   (([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ∧ [𝐴 / 𝑥](𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
36 sbcan 3675 . . . . . . . . . . . . . . . 16 ([𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ∧ [𝐴 / 𝑥](𝑤𝐵𝑦𝐶)))
3736a1i 11 . . . . . . . . . . . . . . 15 (𝐴𝑉 → ([𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ∧ [𝐴 / 𝑥](𝑤𝐵𝑦𝐶))))
381, 37e1a 39611 . . . . . . . . . . . . . 14 (   𝐴𝑉   ▶   ([𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ∧ [𝐴 / 𝑥](𝑤𝐵𝑦𝐶)))   )
39 bibi1 343 . . . . . . . . . . . . . . 15 (([𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ∧ [𝐴 / 𝑥](𝑤𝐵𝑦𝐶))) → (([𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))) ↔ (([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ∧ [𝐴 / 𝑥](𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))))
4039biimprcd 242 . . . . . . . . . . . . . 14 ((([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ∧ [𝐴 / 𝑥](𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))) → (([𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ([𝐴 / 𝑥]𝑧 = ⟨𝑤, 𝑦⟩ ∧ [𝐴 / 𝑥](𝑤𝐵𝑦𝐶))) → ([𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))))
4135, 38, 40e11 39672 . . . . . . . . . . . . 13 (   𝐴𝑉   ▶   ([𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
4241gen11 39600 . . . . . . . . . . . 12 (   𝐴𝑉   ▶   𝑦([𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
43 exbi 1943 . . . . . . . . . . . 12 (∀𝑦([𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ (𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))) → (∃𝑦[𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))))
4442, 43e1a 39611 . . . . . . . . . . 11 (   𝐴𝑉   ▶   (∃𝑦[𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
45 sbcex2 3683 . . . . . . . . . . . . 13 ([𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦[𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)))
4645a1i 11 . . . . . . . . . . . 12 (𝐴𝑉 → ([𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦[𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))))
471, 46e1a 39611 . . . . . . . . . . 11 (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦[𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)))   )
48 bibi1 343 . . . . . . . . . . . 12 (([𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦[𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))) → (([𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))) ↔ (∃𝑦[𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))))
4948biimprcd 242 . . . . . . . . . . 11 ((∃𝑦[𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))) → (([𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦[𝐴 / 𝑥](𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))) → ([𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))))
5044, 47, 49e11 39672 . . . . . . . . . 10 (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
5150gen11 39600 . . . . . . . . 9 (   𝐴𝑉   ▶   𝑤([𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
52 exbi 1943 . . . . . . . . 9 (∀𝑤([𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))) → (∃𝑤[𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))))
5351, 52e1a 39611 . . . . . . . 8 (   𝐴𝑉   ▶   (∃𝑤[𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
54 sbcex2 3683 . . . . . . . . . 10 ([𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤[𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)))
5554a1i 11 . . . . . . . . 9 (𝐴𝑉 → ([𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤[𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))))
561, 55e1a 39611 . . . . . . . 8 (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤[𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)))   )
57 bibi1 343 . . . . . . . . 9 (([𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤[𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))) → (([𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))) ↔ (∃𝑤[𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))))
5857biimprcd 242 . . . . . . . 8 ((∃𝑤[𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))) → (([𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤[𝐴 / 𝑥]𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))) → ([𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))))
5953, 56, 58e11 39672 . . . . . . 7 (   𝐴𝑉   ▶   ([𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
6059gen11 39600 . . . . . 6 (   𝐴𝑉   ▶   𝑧([𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)))   )
61 abbi 2913 . . . . . . 7 (∀𝑧([𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))) ↔ {𝑧[𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))})
6261biimpi 208 . . . . . 6 (∀𝑧([𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶)) ↔ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))) → {𝑧[𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))})
6360, 62e1a 39611 . . . . 5 (   𝐴𝑉   ▶   {𝑧[𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}   )
64 csbab 4203 . . . . . . 7 𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧[𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))}
6564a1i 11 . . . . . 6 (𝐴𝑉𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧[𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))})
661, 65e1a 39611 . . . . 5 (   𝐴𝑉   ▶   𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧[𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))}   )
67 eqeq2 2809 . . . . . 6 ({𝑧[𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))} → (𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧[𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} ↔ 𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}))
6867biimpd 221 . . . . 5 ({𝑧[𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))} → (𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧[𝐴 / 𝑥]𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} → 𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}))
6963, 66, 68e11 39672 . . . 4 (   𝐴𝑉   ▶   𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}   )
70 df-xp 5317 . . . . . . 7 (𝐵 × 𝐶) = {⟨𝑤, 𝑦⟩ ∣ (𝑤𝐵𝑦𝐶)}
71 df-opab 4905 . . . . . . 7 {⟨𝑤, 𝑦⟩ ∣ (𝑤𝐵𝑦𝐶)} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))}
7270, 71eqtri 2820 . . . . . 6 (𝐵 × 𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))}
7372ax-gen 1891 . . . . 5 𝑥(𝐵 × 𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))}
74 csbeq2 3731 . . . . . 6 (∀𝑥(𝐵 × 𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} → 𝐴 / 𝑥(𝐵 × 𝐶) = 𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))})
7574a1i 11 . . . . 5 (𝐴𝑉 → (∀𝑥(𝐵 × 𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} → 𝐴 / 𝑥(𝐵 × 𝐶) = 𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))}))
761, 73, 75e10 39678 . . . 4 (   𝐴𝑉   ▶   𝐴 / 𝑥(𝐵 × 𝐶) = 𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))}   )
77 eqeq2 2809 . . . . 5 (𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))} → (𝐴 / 𝑥(𝐵 × 𝐶) = 𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} ↔ 𝐴 / 𝑥(𝐵 × 𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}))
7877biimpd 221 . . . 4 (𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))} → (𝐴 / 𝑥(𝐵 × 𝐶) = 𝐴 / 𝑥{𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐵𝑦𝐶))} → 𝐴 / 𝑥(𝐵 × 𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}))
7969, 76, 78e11 39672 . . 3 (   𝐴𝑉   ▶   𝐴 / 𝑥(𝐵 × 𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}   )
80 df-xp 5317 . . . 4 (𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶) = {⟨𝑤, 𝑦⟩ ∣ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)}
81 df-opab 4905 . . . 4 {⟨𝑤, 𝑦⟩ ∣ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶)} = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}
8280, 81eqtri 2820 . . 3 (𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}
83 eqeq2 2809 . . . 4 ((𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))} → (𝐴 / 𝑥(𝐵 × 𝐶) = (𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶) ↔ 𝐴 / 𝑥(𝐵 × 𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))}))
8483biimprcd 242 . . 3 (𝐴 / 𝑥(𝐵 × 𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))} → ((𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶) = {𝑧 ∣ ∃𝑤𝑦(𝑧 = ⟨𝑤, 𝑦⟩ ∧ (𝑤𝐴 / 𝑥𝐵𝑦𝐴 / 𝑥𝐶))} → 𝐴 / 𝑥(𝐵 × 𝐶) = (𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶)))
8579, 82, 84e10 39678 . 2 (   𝐴𝑉   ▶   𝐴 / 𝑥(𝐵 × 𝐶) = (𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶)   )
8685in1 39546 1 (𝐴𝑉𝐴 / 𝑥(𝐵 × 𝐶) = (𝐴 / 𝑥𝐵 × 𝐴 / 𝑥𝐶))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 198  wa 385  wal 1651   = wceq 1653  wex 1875  wcel 2157  {cab 2784  [wsbc 3632  csb 3727  cop 4373  {copab 4904   × cxp 5309
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1891  ax-4 1905  ax-5 2006  ax-6 2072  ax-7 2107  ax-9 2166  ax-10 2185  ax-11 2200  ax-12 2213  ax-13 2377  ax-ext 2776
This theorem depends on definitions:  df-bi 199  df-an 386  df-or 875  df-tru 1657  df-fal 1667  df-ex 1876  df-nf 1880  df-sb 2065  df-clab 2785  df-cleq 2791  df-clel 2794  df-nfc 2929  df-v 3386  df-sbc 3633  df-csb 3728  df-dif 3771  df-nul 4115  df-opab 4905  df-xp 5317  df-vd1 39545
This theorem is referenced by: (None)
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