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Theorem hbra1 2496
Description: 𝑥 is not free in 𝑥𝐴𝜑. (Contributed by NM, 18-Oct-1996.)
Assertion
Ref Expression
hbra1 (∀𝑥𝐴 𝜑 → ∀𝑥𝑥𝐴 𝜑)

Proof of Theorem hbra1
StepHypRef Expression
1 df-ral 2449 . 2 (∀𝑥𝐴 𝜑 ↔ ∀𝑥(𝑥𝐴𝜑))
2 hba1 1528 . 2 (∀𝑥(𝑥𝐴𝜑) → ∀𝑥𝑥(𝑥𝐴𝜑))
31, 2hbxfrbi 1460 1 (∀𝑥𝐴 𝜑 → ∀𝑥𝑥𝐴 𝜑)
Colors of variables: wff set class
Syntax hints:  wi 4  wal 1341  wcel 2136  wral 2444
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1435  ax-gen 1437  ax-ial 1522
This theorem depends on definitions:  df-bi 116  df-ral 2449
This theorem is referenced by: (None)
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