Theorem 19.28h 1576

Description: Theorem 19.28 of [Margaris] p. 90. (Contributed by NM, 5-Aug-1993.)

Hypothesis

Ref	Expression
19.28h.1	|- ( ph -> A. x ph )

Assertion

Ref	Expression
19.28h	|- ( A. x ( ph /\ ps ) <-> ( ph /\ A. x ps ) )

Proof of Theorem 19.28h

Step	Hyp	Ref	Expression
1		19.26 1495	. 2 |- ( A. x ( ph /\ ps ) <-> ( A. x ph /\ A. x ps ) )
2		19.28h.1	. . . 4 |- ( ph -> A. x ph )
3	2	19.3h 1567	. . 3 |- ( A. x ph <-> ph )
4	3	anbi1i 458	. 2 |- ( ( A. x ph /\ A. x ps ) <-> ( ph /\ A. x ps ) )
5	1, 4	bitri 184	1 |- ( A. x ( ph /\ ps ) <-> ( ph /\ A. x ps ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   A.wal 1362

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1461  ax-gen 1463  ax-4 1524

This theorem depends on definitions:  df-bi 117

This theorem is referenced by:  nfan1  1578  aaanh  1600  exan  1707  19.28v  1915