Theorem cbvoprab2davw 36211

Description: Change the second bound variable in an operation abstraction. Deduction form. (Contributed by GG, 14-Aug-2025.)

Hypothesis

Ref	Expression
cbvoprab2davw.1	⊢ ((𝜑 ∧ 𝑦 = 𝑤) → (𝜓 ↔ 𝜒))

Assertion

Ref	Expression
cbvoprab2davw	⊢ (𝜑 → {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ 𝜓} = {⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∣ 𝜒})

Distinct variable groups:   𝜑,𝑥,𝑦,𝑤   𝜑,𝑧,𝑦,𝑤   𝜓,𝑤   𝜒,𝑦

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

Proof of Theorem cbvoprab2davw

Dummy variable 𝑡 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		opeq2 4847	. . . . . . . . . 10 ⊢ (𝑦 = 𝑤 → ⟨𝑥, 𝑦⟩ = ⟨𝑥, 𝑤⟩)
2	1	adantl 481	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝑦 = 𝑤) → ⟨𝑥, 𝑦⟩ = ⟨𝑥, 𝑤⟩)
3	2	opeq1d 4852	. . . . . . . 8 ⊢ ((𝜑 ∧ 𝑦 = 𝑤) → ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩)
4	3	eqeq2d 2745	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑦 = 𝑤) → (𝑡 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ↔ 𝑡 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩))
5		cbvoprab2davw.1	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑦 = 𝑤) → (𝜓 ↔ 𝜒))
6	4, 5	anbi12d 632	. . . . . 6 ⊢ ((𝜑 ∧ 𝑦 = 𝑤) → ((𝑡 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜓) ↔ (𝑡 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜒)))
7	6	exbidv 1920	. . . . 5 ⊢ ((𝜑 ∧ 𝑦 = 𝑤) → (∃𝑧(𝑡 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜓) ↔ ∃𝑧(𝑡 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜒)))
8	7	cbvexdvaw 2037	. . . 4 ⊢ (𝜑 → (∃𝑦∃𝑧(𝑡 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜓) ↔ ∃𝑤∃𝑧(𝑡 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜒)))
9	8	exbidv 1920	. . 3 ⊢ (𝜑 → (∃𝑥∃𝑦∃𝑧(𝑡 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜓) ↔ ∃𝑥∃𝑤∃𝑧(𝑡 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜒)))
10	9	abbidv 2800	. 2 ⊢ (𝜑 → {𝑡 ∣ ∃𝑥∃𝑦∃𝑧(𝑡 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜓)} = {𝑡 ∣ ∃𝑥∃𝑤∃𝑧(𝑡 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜒)})
11		df-oprab 7403	. 2 ⊢ {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ 𝜓} = {𝑡 ∣ ∃𝑥∃𝑦∃𝑧(𝑡 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜓)}
12		df-oprab 7403	. 2 ⊢ {⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∣ 𝜒} = {𝑡 ∣ ∃𝑥∃𝑤∃𝑧(𝑡 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜒)}
13	10, 11, 12	3eqtr4g 2794	1 ⊢ (𝜑 → {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ 𝜓} = {⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∣ 𝜒})

Syntax hints:   → wi 4   ↔ wb 206   ∧ wa 395   = wceq 1539  ∃wex 1778  {cab 2712  ⟨cop 4605  {coprab 7400

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1794  ax-4 1808  ax-5 1909  ax-6 1966  ax-7 2006  ax-8 2109  ax-9 2117  ax-ext 2706

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1542  df-fal 1552  df-ex 1779  df-sb 2064  df-clab 2713  df-cleq 2726  df-clel 2808  df-rab 3414  df-v 3459  df-dif 3927  df-un 3929  df-ss 3941  df-nul 4307  df-if 4499  df-sn 4600  df-pr 4602  df-op 4606  df-oprab 7403

This theorem is referenced by:  cbvmpo2davw2  36232