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Theorem r19.32r 2697
Description: One direction of Theorem 19.32 of [Margaris] p. 90 with restricted quantifiers. For decidable propositions this is an equivalence. (Contributed by Jim Kingdon, 19-Aug-2018.)
Hypothesis
Ref Expression
r19.32r.1 Ⅎ𝑥𝜑
Assertion
Ref Expression
r19.32r ((𝜑 ∨ ∀𝑥 ∈ 𝐴 𝜓) → ∀𝑥 ∈ 𝐴 (𝜑 ∨ 𝜓))

Proof of Theorem r19.32r
StepHypRef Expression
1 r19.32r.1 . . . 4 Ⅎ𝑥𝜑
2 orc 724 . . . . 5 (𝜑 → (𝜑 ∨ 𝜓))
32a1d 22 . . . 4 (𝜑 → (𝑥 ∈ 𝐴 → (𝜑 ∨ 𝜓)))
41, 3alrimi 1575 . . 3 (𝜑 → ∀𝑥(𝑥 ∈ 𝐴 → (𝜑 ∨ 𝜓)))
5 df-ral 2533 . . . 4 (∀𝑥 ∈ 𝐴 𝜓 ↔ ∀𝑥(𝑥 ∈ 𝐴 → 𝜓))
6 olc 723 . . . . . 6 (𝜓 → (𝜑 ∨ 𝜓))
76imim2i 12 . . . . 5 ((𝑥 ∈ 𝐴 → 𝜓) → (𝑥 ∈ 𝐴 → (𝜑 ∨ 𝜓)))
87alimi 1508 . . . 4 (∀𝑥(𝑥 ∈ 𝐴 → 𝜓) → ∀𝑥(𝑥 ∈ 𝐴 → (𝜑 ∨ 𝜓)))
95, 8sylbi 121 . . 3 (∀𝑥 ∈ 𝐴 𝜓 → ∀𝑥(𝑥 ∈ 𝐴 → (𝜑 ∨ 𝜓)))
104, 9jaoi 728 . 2 ((𝜑 ∨ ∀𝑥 ∈ 𝐴 𝜓) → ∀𝑥(𝑥 ∈ 𝐴 → (𝜑 ∨ 𝜓)))
11 df-ral 2533 . 2 (∀𝑥 ∈ 𝐴 (𝜑 ∨ 𝜓) ↔ ∀𝑥(𝑥 ∈ 𝐴 → (𝜑 ∨ 𝜓)))
1210, 11sylibr 134 1 ((𝜑 ∨ ∀𝑥 ∈ 𝐴 𝜓) → ∀𝑥 ∈ 𝐴 (𝜑 ∨ 𝜓))
Colors of variables:    wff set class
This proof depends on syntax axioms:   → wi 4   ∨ wo 720  ∀wal 1400  Ⅎwnf 1513   ∈ wcel 2209  ∀wral 2528
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 721  ax-5 1500  ax-gen 1502  ax-4 1563
This proof depends on definitions:  df-bi 117  df-nf 1514  df-ral 2533
This theorem is used by:  r19.32vr  2699
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