Theorem cbvoprab12 7364

Description: Rule used to change first two bound variables in an operation abstraction, using implicit substitution. (Contributed by NM, 21-Feb-2004.) (Proof shortened by Andrew Salmon, 22-Oct-2011.)

Hypotheses

Ref	Expression
cbvoprab12.1	⊢ Ⅎ𝑤𝜑
cbvoprab12.2	⊢ Ⅎ𝑣𝜑
cbvoprab12.3	⊢ Ⅎ𝑥𝜓
cbvoprab12.4	⊢ Ⅎ𝑦𝜓
cbvoprab12.5	⊢ ((𝑥 = 𝑤 ∧ 𝑦 = 𝑣) → (𝜑 ↔ 𝜓))

Assertion

Ref	Expression
cbvoprab12	⊢ {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ 𝜑} = {⟨⟨𝑤, 𝑣⟩, 𝑧⟩ ∣ 𝜓}

Distinct variable group:   𝑥,𝑦,𝑧,𝑤,𝑣

Allowed substitution hints:   𝜑(𝑥,𝑦,𝑧,𝑤,𝑣)   𝜓(𝑥,𝑦,𝑧,𝑤,𝑣)

Proof of Theorem cbvoprab12

Dummy variable 𝑢 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		nfv 1917	. . . . 5 ⊢ Ⅎ𝑤 𝑢 = ⟨𝑥, 𝑦⟩
2		cbvoprab12.1	. . . . 5 ⊢ Ⅎ𝑤𝜑
3	1, 2	nfan 1902	. . . 4 ⊢ Ⅎ𝑤(𝑢 = ⟨𝑥, 𝑦⟩ ∧ 𝜑)
4		nfv 1917	. . . . 5 ⊢ Ⅎ𝑣 𝑢 = ⟨𝑥, 𝑦⟩
5		cbvoprab12.2	. . . . 5 ⊢ Ⅎ𝑣𝜑
6	4, 5	nfan 1902	. . . 4 ⊢ Ⅎ𝑣(𝑢 = ⟨𝑥, 𝑦⟩ ∧ 𝜑)
7		nfv 1917	. . . . 5 ⊢ Ⅎ𝑥 𝑢 = ⟨𝑤, 𝑣⟩
8		cbvoprab12.3	. . . . 5 ⊢ Ⅎ𝑥𝜓
9	7, 8	nfan 1902	. . . 4 ⊢ Ⅎ𝑥(𝑢 = ⟨𝑤, 𝑣⟩ ∧ 𝜓)
10		nfv 1917	. . . . 5 ⊢ Ⅎ𝑦 𝑢 = ⟨𝑤, 𝑣⟩
11		cbvoprab12.4	. . . . 5 ⊢ Ⅎ𝑦𝜓
12	10, 11	nfan 1902	. . . 4 ⊢ Ⅎ𝑦(𝑢 = ⟨𝑤, 𝑣⟩ ∧ 𝜓)
13		opeq12 4806	. . . . . 6 ⊢ ((𝑥 = 𝑤 ∧ 𝑦 = 𝑣) → ⟨𝑥, 𝑦⟩ = ⟨𝑤, 𝑣⟩)
14	13	eqeq2d 2749	. . . . 5 ⊢ ((𝑥 = 𝑤 ∧ 𝑦 = 𝑣) → (𝑢 = ⟨𝑥, 𝑦⟩ ↔ 𝑢 = ⟨𝑤, 𝑣⟩))
15		cbvoprab12.5	. . . . 5 ⊢ ((𝑥 = 𝑤 ∧ 𝑦 = 𝑣) → (𝜑 ↔ 𝜓))
16	14, 15	anbi12d 631	. . . 4 ⊢ ((𝑥 = 𝑤 ∧ 𝑦 = 𝑣) → ((𝑢 = ⟨𝑥, 𝑦⟩ ∧ 𝜑) ↔ (𝑢 = ⟨𝑤, 𝑣⟩ ∧ 𝜓)))
17	3, 6, 9, 12, 16	cbvex2v 2342	. . 3 ⊢ (∃𝑥∃𝑦(𝑢 = ⟨𝑥, 𝑦⟩ ∧ 𝜑) ↔ ∃𝑤∃𝑣(𝑢 = ⟨𝑤, 𝑣⟩ ∧ 𝜓))
18	17	opabbii 5141	. 2 ⊢ {⟨𝑢, 𝑧⟩ ∣ ∃𝑥∃𝑦(𝑢 = ⟨𝑥, 𝑦⟩ ∧ 𝜑)} = {⟨𝑢, 𝑧⟩ ∣ ∃𝑤∃𝑣(𝑢 = ⟨𝑤, 𝑣⟩ ∧ 𝜓)}
19		dfoprab2 7333	. 2 ⊢ {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ 𝜑} = {⟨𝑢, 𝑧⟩ ∣ ∃𝑥∃𝑦(𝑢 = ⟨𝑥, 𝑦⟩ ∧ 𝜑)}
20		dfoprab2 7333	. 2 ⊢ {⟨⟨𝑤, 𝑣⟩, 𝑧⟩ ∣ 𝜓} = {⟨𝑢, 𝑧⟩ ∣ ∃𝑤∃𝑣(𝑢 = ⟨𝑤, 𝑣⟩ ∧ 𝜓)}
21	18, 19, 20	3eqtr4i 2776	1 ⊢ {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ 𝜑} = {⟨⟨𝑤, 𝑣⟩, 𝑧⟩ ∣ 𝜓}

Syntax hints:   → wi 4   ↔ wb 205   ∧ wa 396   = wceq 1539  ∃wex 1782  Ⅎwnf 1786  ⟨cop 4567  {copab 5136  {coprab 7276

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2709  ax-sep 5223  ax-nul 5230  ax-pr 5352

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 845  df-3an 1088  df-tru 1542  df-fal 1552  df-ex 1783  df-nf 1787  df-sb 2068  df-clab 2716  df-cleq 2730  df-clel 2816  df-rab 3073  df-v 3434  df-dif 3890  df-un 3892  df-nul 4257  df-if 4460  df-sn 4562  df-pr 4564  df-op 4568  df-opab 5137  df-oprab 7279

This theorem is referenced by:  cbvoprab12v  7365  cbvmpox  7368  dfoprab4f  7896  fmpox  7907  tposoprab  8078  f1od2  31056  cbvmpox2  45671