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Theorem rab0 3525
Description: Any restricted class abstraction restricted to the empty set is empty. (Contributed by NM, 15-Oct-2003.) (Proof shortened by Andrew Salmon, 26-Jun-2011.)
Assertion
Ref Expression
rab0 {𝑥 ∈ ∅ ∣ 𝜑} = ∅

Proof of Theorem rab0
StepHypRef Expression
1 noel 3500 . . . . 5 ¬ 𝑥 ∈ ∅
21intnanr 938 . . . 4 ¬ (𝑥 ∈ ∅ ∧ 𝜑)
3 equid 1749 . . . . 5 𝑥 = 𝑥
43notnoti 650 . . . 4 ¬ ¬ 𝑥 = 𝑥
52, 42false 709 . . 3 ((𝑥 ∈ ∅ ∧ 𝜑) ↔ ¬ 𝑥 = 𝑥)
65abbii 2347 . 2 {𝑥 ∣ (𝑥 ∈ ∅ ∧ 𝜑)} = {𝑥 ∣ ¬ 𝑥 = 𝑥}
7 df-rab 2520 . 2 {𝑥 ∈ ∅ ∣ 𝜑} = {𝑥 ∣ (𝑥 ∈ ∅ ∧ 𝜑)}
8 dfnul2 3498 . 2 ∅ = {𝑥 ∣ ¬ 𝑥 = 𝑥}
96, 7, 83eqtr4i 2262 1 {𝑥 ∈ ∅ ∣ 𝜑} = ∅
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wa 104   = wceq 1398  wcel 2202  {cab 2217  {crab 2515  c0 3496
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 619  ax-in2 620  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-ext 2213
This theorem depends on definitions:  df-bi 117  df-tru 1401  df-nf 1510  df-sb 1811  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2364  df-rab 2520  df-v 2805  df-dif 3203  df-nul 3497
This theorem is referenced by:  if0ab  3610  supp0  6416  ssfirab  7172  sup00  7245  vtxdgfi0e  16219  clwwlk0on0  16355
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