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Theorem 19.27h 1492
Description: Theorem 19.27 of [Margaris] p. 90. (Contributed by NM, 5-Aug-1993.)
Hypothesis
Ref Expression
19.27h.1 (𝜓 → ∀𝑥𝜓)
Assertion
Ref Expression
19.27h (∀𝑥(𝜑𝜓) ↔ (∀𝑥𝜑𝜓))

Proof of Theorem 19.27h
StepHypRef Expression
1 19.26 1410 . 2 (∀𝑥(𝜑𝜓) ↔ (∀𝑥𝜑 ∧ ∀𝑥𝜓))
2 19.27h.1 . . . 4 (𝜓 → ∀𝑥𝜓)
3219.3h 1485 . . 3 (∀𝑥𝜓𝜓)
43anbi2i 444 . 2 ((∀𝑥𝜑 ∧ ∀𝑥𝜓) ↔ (∀𝑥𝜑𝜓))
51, 4bitri 182 1 (∀𝑥(𝜑𝜓) ↔ (∀𝑥𝜑𝜓))
Colors of variables: wff set class
Syntax hints:  wi 4  wa 102  wb 103  wal 1282
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-5 1376  ax-gen 1378  ax-4 1440
This theorem depends on definitions:  df-bi 115
This theorem is referenced by:  aaanh  1518  19.27v  1820
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