Theorem nfrab1 2608

Description: The abstraction variable in a restricted class abstraction isn't free. (Contributed by NM, 19-Mar-1997.)

Assertion

Ref	Expression
nfrab1	⊢ Ⅎ𝑥{𝑥 ∈ 𝐴 ∣ 𝜑}

Proof of Theorem nfrab1

Step	Hyp	Ref	Expression
1		df-rab 2423	. 2 ⊢ {𝑥 ∈ 𝐴 ∣ 𝜑} = {𝑥 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)}
2		nfab1 2281	. 2 ⊢ Ⅎ𝑥{𝑥 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)}
3	1, 2	nfcxfr 2276	1 ⊢ Ⅎ𝑥{𝑥 ∈ 𝐴 ∣ 𝜑}

Syntax hints:   ∧ wa 103   ∈ wcel 1480  {cab 2123  Ⅎwnfc 2266  {crab 2418

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1423  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-11 1484  ax-4 1487  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-ext 2119

This theorem depends on definitions:  df-bi 116  df-nf 1437  df-sb 1736  df-clab 2124  df-cleq 2130  df-clel 2133  df-nfc 2268  df-rab 2423

This theorem is referenced by:  repizf2  4081  rabxfrd  4385  onintrab2im  4429  tfis  4492  fvmptssdm  5498  infssuzcldc  11633  imasnopn  12457