MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  cbvoprab2 Structured version   Visualization version   GIF version

Theorem cbvoprab2 7234
Description: Change the second bound variable in an operation abstraction. (Contributed by Jeff Madsen, 11-Jun-2010.) (Revised by Mario Carneiro, 11-Dec-2016.)
Hypotheses
Ref Expression
cbvoprab2.1 𝑤𝜑
cbvoprab2.2 𝑦𝜓
cbvoprab2.3 (𝑦 = 𝑤 → (𝜑𝜓))
Assertion
Ref Expression
cbvoprab2 {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ 𝜑} = {⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∣ 𝜓}
Distinct variable group:   𝑥,𝑤,𝑦,𝑧
Allowed substitution hints:   𝜑(𝑥,𝑦,𝑧,𝑤)   𝜓(𝑥,𝑦,𝑧,𝑤)

Proof of Theorem cbvoprab2
Dummy variable 𝑣 is distinct from all other variables.
StepHypRef Expression
1 nfv 1908 . . . . . . 7 𝑤 𝑣 = ⟨⟨𝑥, 𝑦⟩, 𝑧
2 cbvoprab2.1 . . . . . . 7 𝑤𝜑
31, 2nfan 1893 . . . . . 6 𝑤(𝑣 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜑)
43nfex 2336 . . . . 5 𝑤𝑧(𝑣 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜑)
5 nfv 1908 . . . . . . 7 𝑦 𝑣 = ⟨⟨𝑥, 𝑤⟩, 𝑧
6 cbvoprab2.2 . . . . . . 7 𝑦𝜓
75, 6nfan 1893 . . . . . 6 𝑦(𝑣 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜓)
87nfex 2336 . . . . 5 𝑦𝑧(𝑣 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜓)
9 opeq2 4796 . . . . . . . . 9 (𝑦 = 𝑤 → ⟨𝑥, 𝑦⟩ = ⟨𝑥, 𝑤⟩)
109opeq1d 4801 . . . . . . . 8 (𝑦 = 𝑤 → ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩)
1110eqeq2d 2830 . . . . . . 7 (𝑦 = 𝑤 → (𝑣 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ↔ 𝑣 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩))
12 cbvoprab2.3 . . . . . . 7 (𝑦 = 𝑤 → (𝜑𝜓))
1311, 12anbi12d 632 . . . . . 6 (𝑦 = 𝑤 → ((𝑣 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜑) ↔ (𝑣 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜓)))
1413exbidv 1915 . . . . 5 (𝑦 = 𝑤 → (∃𝑧(𝑣 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜑) ↔ ∃𝑧(𝑣 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜓)))
154, 8, 14cbvexv1 2355 . . . 4 (∃𝑦𝑧(𝑣 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜑) ↔ ∃𝑤𝑧(𝑣 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜓))
1615exbii 1841 . . 3 (∃𝑥𝑦𝑧(𝑣 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜑) ↔ ∃𝑥𝑤𝑧(𝑣 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜓))
1716abbii 2884 . 2 {𝑣 ∣ ∃𝑥𝑦𝑧(𝑣 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜑)} = {𝑣 ∣ ∃𝑥𝑤𝑧(𝑣 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜓)}
18 df-oprab 7152 . 2 {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ 𝜑} = {𝑣 ∣ ∃𝑥𝑦𝑧(𝑣 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ 𝜑)}
19 df-oprab 7152 . 2 {⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∣ 𝜓} = {𝑣 ∣ ∃𝑥𝑤𝑧(𝑣 = ⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∧ 𝜓)}
2017, 18, 193eqtr4i 2852 1 {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ 𝜑} = {⟨⟨𝑥, 𝑤⟩, 𝑧⟩ ∣ 𝜓}
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 208  wa 398   = wceq 1530  wex 1773  wnf 1777  {cab 2797  cop 4565  {coprab 7149
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1789  ax-4 1803  ax-5 1904  ax-6 1963  ax-7 2008  ax-8 2109  ax-9 2117  ax-10 2138  ax-11 2153  ax-12 2169  ax-ext 2791
This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3an 1083  df-tru 1533  df-ex 1774  df-nf 1778  df-sb 2063  df-clab 2798  df-cleq 2812  df-clel 2891  df-nfc 2961  df-rab 3145  df-v 3495  df-dif 3937  df-un 3939  df-in 3941  df-ss 3950  df-nul 4290  df-if 4466  df-sn 4560  df-pr 4562  df-op 4566  df-oprab 7152
This theorem is referenced by:  cbvmpo2  41353
  Copyright terms: Public domain W3C validator