Theorem 19.19 1959

Description: Theorem 19.19 of [Margaris] p. 90. (Contributed by NM, 12-Mar-1993.)

Hypothesis

Ref	Expression
19.19.1

Assertion

Ref	Expression
19.19

Proof of Theorem 19.19

Step	Hyp	Ref	Expression
1		19.19.1	. . 3
2	1	19.9 1893	. 2
3		exbi 1666	. 2
4	2, 3	syl5bbr 259	1

Syntax hints:  ->wi 4  <->wb 184  A.wal 1393  E.wex 1612  F/wnf 1616

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-ex 1613  df-nf 1617