Theorem nfreuw 3397

Description: Bound-variable hypothesis builder for restricted unique existence. Version of nfreu 3413 with a disjoint variable condition, which does not require ax-13 2403. (Contributed by NM, 30-Oct-2010.) Avoid ax-13 2403. (Revised by GG, 10-Jan-2024.) Avoid ax-9 2155, ax-ext 2734. (Revised by Wolf Lammen, 21-Nov-2024.)

Hypotheses

Ref	Expression
nfrmow.1	⊢ Ⅎ𝑥𝐴
nfrmow.2	⊢ Ⅎ𝑥𝜑

Assertion

Ref	Expression
nfreuw	⊢ Ⅎ𝑥∃!𝑦 ∈ 𝐴 𝜑

Distinct variable group:   𝑥,𝑦

Allowed substitution hints:   𝜑(𝑥, 𝑦)   𝐴(𝑥, 𝑦)

Proof of Theorem nfreuw

Step	Hyp	Ref	Expression
1		df-reu 3368	. 2 ⊢ (∃!𝑦 ∈ 𝐴 𝜑 ↔ ∃!𝑦(𝑦 ∈ 𝐴 ∧ 𝜑))
2		nfrmow.1	. . . . 5 ⊢ Ⅎ𝑥𝐴
3	2	nfcri 2916	. . . 4 ⊢ Ⅎ𝑥 𝑦 ∈ 𝐴
4		nfrmow.2	. . . 4 ⊢ Ⅎ𝑥𝜑
5	3, 4	nfan 1932	. . 3 ⊢ Ⅎ𝑥(𝑦 ∈ 𝐴 ∧ 𝜑)
6	5	nfeuw 2620	. 2 ⊢ Ⅎ𝑥∃!𝑦(𝑦 ∈ 𝐴 ∧ 𝜑)
7	1, 6	nfxfr 1886	1 ⊢ Ⅎ𝑥∃!𝑦 ∈ 𝐴 𝜑

This proof depends on syntax axioms:   ∧ wa 401  Ⅎwnf 1816   ∈ wcel 2145  ∃!weu 2595  Ⅎwnfc 2909  ∃!wreu 3365

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-10 2178  ax-11 2194  ax-12 2215

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-tru 1573  df-ex 1813  df-nf 1817  df-mo 2566  df-eu 2596  df-clel 2837  df-nfc 2911  df-reu 3368

This theorem is used by:  sbcreu  3826  reuccatpfxs1  14818  2reu7  47986  2reu8  47987  nfralseu  50751