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Theorem dfrals2 17038
Description: The bounded "all some" form is the general form with the class membership folded into the antecedent. (Contributed by David A. Wheeler, 22-Oct-2018.) (Revised by David A. Wheeler, 12-Jul-2026.)
Assertion
Ref Expression
dfrals2 (∀∃𝑥𝐴(𝜑𝜓) ↔ ∀∃𝑥((𝑥𝐴𝜑) → 𝜓))

Proof of Theorem dfrals2
StepHypRef Expression
1 df-ral 2533 . . . 4 (∀𝑥𝐴 (𝜑𝜓) ↔ ∀𝑥(𝑥𝐴 → (𝜑𝜓)))
2 impexp 263 . . . . 5 (((𝑥𝐴𝜑) → 𝜓) ↔ (𝑥𝐴 → (𝜑𝜓)))
32albii 1523 . . . 4 (∀𝑥((𝑥𝐴𝜑) → 𝜓) ↔ ∀𝑥(𝑥𝐴 → (𝜑𝜓)))
41, 3bitr4i 187 . . 3 (∀𝑥𝐴 (𝜑𝜓) ↔ ∀𝑥((𝑥𝐴𝜑) → 𝜓))
5 df-rex 2534 . . 3 (∃𝑥𝐴 𝜑 ↔ ∃𝑥(𝑥𝐴𝜑))
64, 5anbi12i 464 . 2 ((∀𝑥𝐴 (𝜑𝜓) ∧ ∃𝑥𝐴 𝜑) ↔ (∀𝑥((𝑥𝐴𝜑) → 𝜓) ∧ ∃𝑥(𝑥𝐴𝜑)))
7 df-rals 17037 . 2 (∀∃𝑥𝐴(𝜑𝜓) ↔ (∀𝑥𝐴 (𝜑𝜓) ∧ ∃𝑥𝐴 𝜑))
8 df-als 17036 . 2 (∀∃𝑥((𝑥𝐴𝜑) → 𝜓) ↔ (∀𝑥((𝑥𝐴𝜑) → 𝜓) ∧ ∃𝑥(𝑥𝐴𝜑)))
96, 7, 83bitr4i 212 1 (∀∃𝑥𝐴(𝜑𝜓) ↔ ∀∃𝑥((𝑥𝐴𝜑) → 𝜓))
Colors of variables: wff set class
Syntax hints:  wi 4  wa 104  wb 105  wal 1400  wex 1545  wcel 2209  wral 2528  wrex 2529  ∀∃wals 17034  ∀∃wrals 17035
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1500  ax-gen 1502
This theorem depends on definitions:  df-bi 117  df-ral 2533  df-rex 2534  df-als 17036  df-rals 17037
This theorem is referenced by:  rals-no-surprise  17056
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