Theorem 19.32 1967

Description: Theorem 19.32 of [Margaris] p. 90. See 19.32v 1730 for a version requiring fewer axioms. (Contributed by NM, 14-May-1993.) (Revised by Mario Carneiro, 24-Sep-2016.)

Hypothesis

Ref	Expression
19.32.1

Assertion

Ref	Expression
19.32

Proof of Theorem 19.32

Step	Hyp	Ref	Expression
1		19.32.1	. . . 4
2	1	nfn 1901	. . 3
3	2	19.21 1905	. 2
4		df-or 370	. . 3
5	4	albii 1640	. 2
6		df-or 370	. 2
7	3, 5, 6	3bitr4i 277	1

Syntax hints:  -.wn 3  ->wi 4  <->wb 184  \/wo 368  A.wal 1393  F/wnf 1616

This theorem is referenced by:  19.31  1968  2eu3  2379  axi12  2433

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1618  ax-4 1631  ax-5 1704  ax-6 1747  ax-7 1790  ax-10 1837  ax-12 1854

This theorem depends on definitions:  df-bi 185  df-or 370  df-ex 1613  df-nf 1617