Theorem nfrab1 2489

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 2315	. 2 ⊢ {𝑥 ∈ 𝐴 ∣ 𝜑} = {𝑥 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)}
2		nfab1 2180	. 2 ⊢ Ⅎ𝑥{𝑥 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)}
3	1, 2	nfcxfr 2175	1 ⊢ Ⅎ𝑥{𝑥 ∈ 𝐴 ∣ 𝜑}

Syntax hints:   ∧ wa 97   ∈ wcel 1393  {cab 2026  Ⅎwnfc 2165  {crab 2310

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-5 1336  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-11 1397  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-ext 2022

This theorem depends on definitions:  df-bi 110  df-nf 1350  df-sb 1646  df-clab 2027  df-cleq 2033  df-clel 2036  df-nfc 2167  df-rab 2315

This theorem is referenced by:  repizf2  3915  rabxfrd  4201  onintrab2im  4244  tfis  4306  fvmptssdm  5255