Theorem r19.32 47863

Description: Theorem 19.32 of [Margaris] p. 90 with restricted quantifiers, analogous to r19.32v 3197. (Contributed by Alexander van der Vekens, 29-Jun-2017.)

Hypothesis

Ref	Expression
r19.32.1	⊢ Ⅎ𝑥𝜑

Assertion

Ref	Expression
r19.32	⊢ (∀𝑥 ∈ 𝐴 (𝜑 ∨ 𝜓) ↔ (𝜑 ∨ ∀𝑥 ∈ 𝐴 𝜓))

Proof of Theorem r19.32

Step	Hyp	Ref	Expression
1		r19.32.1	. . . 4 ⊢ Ⅎ𝑥𝜑
2	1	nfn 1886	. . 3 ⊢ Ⅎ𝑥 ¬ 𝜑
3	2	r19.21 3259	. 2 ⊢ (∀𝑥 ∈ 𝐴 (¬ 𝜑 → 𝜓) ↔ (¬ 𝜑 → ∀𝑥 ∈ 𝐴 𝜓))
4		df-or 861	. . 3 ⊢ ((𝜑 ∨ 𝜓) ↔ (¬ 𝜑 → 𝜓))
5	4	ralbii 3110	. 2 ⊢ (∀𝑥 ∈ 𝐴 (𝜑 ∨ 𝜓) ↔ ∀𝑥 ∈ 𝐴 (¬ 𝜑 → 𝜓))
6		df-or 861	. 2 ⊢ ((𝜑 ∨ ∀𝑥 ∈ 𝐴 𝜓) ↔ (¬ 𝜑 → ∀𝑥 ∈ 𝐴 𝜓))
7	3, 5, 6	3bitr4i 306	1 ⊢ (∀𝑥 ∈ 𝐴 (𝜑 ∨ 𝜓) ↔ (𝜑 ∨ ∀𝑥 ∈ 𝐴 𝜓))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ↔ wb 209   ∨ wo 860  Ⅎwnf 1812  ∀wral 3078

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1824  ax-4 1838  ax-5 1939  ax-6 1996  ax-7 2037  ax-12 2212

This proof depends on definitions:  df-bi 210  df-or 861  df-ex 1809  df-nf 1813  df-ral 3079

This theorem is used by:  2reu3  47875