Theorem nfrals 50462

Description: Bound-variable hypothesis builder for "all some" restricted to a class. (Contributed by David A. Wheeler, 12-Jul-2026.)

Hypotheses

Ref	Expression
nfrals.1	⊢ Ⅎ𝑥𝐴
nfrals.2	⊢ Ⅎ𝑥𝜑
nfrals.3	⊢ Ⅎ𝑥𝜓

Assertion

Ref	Expression
nfrals	⊢ Ⅎ𝑥∀∃𝑦 ∈ 𝐴(𝜑 → 𝜓)

Distinct variable group:   𝑥,𝑦

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

Proof of Theorem nfrals

Step	Hyp	Ref	Expression
1		df-rals 50447	. 2 ⊢ (∀∃𝑦 ∈ 𝐴(𝜑 → 𝜓) ↔ (∀𝑦 ∈ 𝐴 (𝜑 → 𝜓) ∧ ∃𝑦 ∈ 𝐴 𝜑))
2		nfrals.1	. . . 4 ⊢ Ⅎ𝑥𝐴
3		nfrals.2	. . . . 5 ⊢ Ⅎ𝑥𝜑
4		nfrals.3	. . . . 5 ⊢ Ⅎ𝑥𝜓
5	3, 4	nfim 1923	. . . 4 ⊢ Ⅎ𝑥(𝜑 → 𝜓)
6	2, 5	nfralw 3318	. . 3 ⊢ Ⅎ𝑥∀𝑦 ∈ 𝐴 (𝜑 → 𝜓)
7	2, 3	nfrexw 3319	. . 3 ⊢ Ⅎ𝑥∃𝑦 ∈ 𝐴 𝜑
8	6, 7	nfan 1926	. 2 ⊢ Ⅎ𝑥(∀𝑦 ∈ 𝐴 (𝜑 → 𝜓) ∧ ∃𝑦 ∈ 𝐴 𝜑)
9	1, 8	nfxfr 1880	1 ⊢ Ⅎ𝑥∀∃𝑦 ∈ 𝐴(𝜑 → 𝜓)

Syntax hints:   → wi 4   ∧ wa 400  Ⅎwnf 1810  Ⅎwnfc 2916  ∀wral 3085  ∃wrex 3095  ∀∃wrals 50445

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1822  ax-4 1836  ax-5 1937  ax-6 1994  ax-7 2035  ax-8 2151  ax-10 2182  ax-11 2198  ax-12 2219

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-tru 1570  df-ex 1807  df-nf 1811  df-clel 2844  df-nfc 2918  df-ral 3086  df-rex 3096  df-rals 50447

This theorem is referenced by: (None)