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Theorem ralrals 17316
Description: If the universal part of a restricted "all some" statement holds, then the statement reduces to the existence of a member of 𝐴 satisfying its antecedent. This is the restricted counterpart of ralals 17322. (Contributed by Peter Mazsa and David A. Wheeler, 20-Jul-2026.)
Assertion
Ref Expression
ralrals (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) → (∀∃𝑥 ∈ 𝐴(𝜑 → 𝜓) ↔ ∃𝑥 ∈ 𝐴 𝜑))

Proof of Theorem ralrals
StepHypRef Expression
1 df-rals 17296 . 2 (∀∃𝑥 ∈ 𝐴(𝜑 → 𝜓) ↔ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ∧ ∃𝑥 ∈ 𝐴 𝜑))
2 ibar 301 . . 3 (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) → (∃𝑥 ∈ 𝐴 𝜑 ↔ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ∧ ∃𝑥 ∈ 𝐴 𝜑)))
32bicomd 141 . 2 (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) → ((∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ∧ ∃𝑥 ∈ 𝐴 𝜑) ↔ ∃𝑥 ∈ 𝐴 𝜑))
41, 3bitrid 192 1 (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) → (∀∃𝑥 ∈ 𝐴(𝜑 → 𝜓) ↔ ∃𝑥 ∈ 𝐴 𝜑))
Colors of variables:    wff set class
This proof depends on syntax axioms:   → wi 4   ∧ wa 104   ↔ wb 105  ∀wral 2528  ∃wrex 2529  ∀∃wrals 17294
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108
This proof depends on definitions:  df-bi 117  df-rals 17296
This theorem is used by: (None)
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