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Theorem hbra1 2664
Description: x is not free in x Aφ. (Contributed by NM, 18-Oct-1996.)
Assertion
Ref Expression
hbra1 (x A φxx A φ)

Proof of Theorem hbra1
StepHypRef Expression
1 df-ral 2620 . 2 (x A φx(x Aφ))
2 hba1 1786 . 2 (x(x Aφ) → xx(x Aφ))
31, 2hbxfrbi 1568 1 (x A φxx A φ)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wal 1540   wcel 1710  wral 2615
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-11 1746
This theorem depends on definitions:  df-bi 177  df-ex 1542  df-ral 2620
This theorem is referenced by: (None)
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