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Theorem nfopabd 5179
Description: Bound-variable hypothesis builder for class abstraction. Deduction form. (Contributed by Scott Fenton, 26-Oct-2024.)
Hypotheses
Ref Expression
nfopabd.1 𝑥𝜑
nfopabd.2 𝑦𝜑
nfopabd.4 (𝜑 → Ⅎ𝑧𝜓)
Assertion
Ref Expression
nfopabd (𝜑𝑧{⟨𝑥, 𝑦⟩ ∣ 𝜓})
Distinct variable groups:   𝑥,𝑧   𝑦,𝑧
Allowed substitution hints:   𝜑(𝑥,𝑦,𝑧)   𝜓(𝑥,𝑦,𝑧)

Proof of Theorem nfopabd
Dummy variable 𝑤 is distinct from all other variables.
StepHypRef Expression
1 df-opab 5174 . 2 {⟨𝑥, 𝑦⟩ ∣ 𝜓} = {𝑤 ∣ ∃𝑥𝑦(𝑤 = ⟨𝑥, 𝑦⟩ ∧ 𝜓)}
2 nfv 1944 . . 3 𝑤𝜑
3 nfopabd.1 . . . 4 𝑥𝜑
4 nfopabd.2 . . . . 5 𝑦𝜑
5 nfvd 1945 . . . . . 6 (𝜑 → Ⅎ𝑧 𝑤 = ⟨𝑥, 𝑦⟩)
6 nfopabd.4 . . . . . 6 (𝜑 → Ⅎ𝑧𝜓)
75, 6nfand 1927 . . . . 5 (𝜑 → Ⅎ𝑧(𝑤 = ⟨𝑥, 𝑦⟩ ∧ 𝜓))
84, 7nfexd 2362 . . . 4 (𝜑 → Ⅎ𝑧𝑦(𝑤 = ⟨𝑥, 𝑦⟩ ∧ 𝜓))
93, 8nfexd 2362 . . 3 (𝜑 → Ⅎ𝑧𝑥𝑦(𝑤 = ⟨𝑥, 𝑦⟩ ∧ 𝜓))
102, 9nfabdw 2946 . 2 (𝜑𝑧{𝑤 ∣ ∃𝑥𝑦(𝑤 = ⟨𝑥, 𝑦⟩ ∧ 𝜓)})
111, 10nfcxfrd 2924 1 (𝜑𝑧{⟨𝑥, 𝑦⟩ ∣ 𝜓})
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 400   = wceq 1570  wex 1809  wnf 1813  {cab 2741  wnfc 2910  cop 4595  {copab 5173
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1825  ax-4 1839  ax-5 1940  ax-6 1997  ax-7 2038  ax-8 2145  ax-9 2153  ax-10 2176  ax-11 2192  ax-12 2213  ax-ext 2735
This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-ex 1810  df-nf 1814  df-sb 2097  df-clab 2742  df-cleq 2755  df-clel 2838  df-nfc 2912  df-opab 5174
This theorem is referenced by:  nfopab  5180  nfttrcld  9675
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