Theorem nfa2 1566

Description: Lemma 24 of [Monk2] p. 114. (Contributed by Mario Carneiro, 24-Sep-2016.)

Assertion

Ref	Expression
nfa2	⊢ Ⅎ𝑥∀𝑦∀𝑥𝜑

Proof of Theorem nfa2

Step	Hyp	Ref	Expression
1		nfa1 1528	. 2 ⊢ Ⅎ𝑥∀𝑥𝜑
2	1	nfal 1563	1 ⊢ Ⅎ𝑥∀𝑦∀𝑥𝜑

Syntax hints:  ∀wal 1340  Ⅎwnf 1447

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 1434  ax-7 1435  ax-gen 1436  ax-ial 1521

This theorem depends on definitions:  df-bi 116  df-nf 1448

This theorem is referenced by:  cbv1h  1733  csbie2t  3088  copsex2t  4217  fnoprabg  5934