Theorem dral2 1667

Description: Formula-building lemma for use with the Distinctor Reduction Theorem. Part of Theorem 9.4 of [Megill] p. 448 (p. 16 of preprint). (Contributed by NM, 27-Feb-2005.)

Hypothesis

Ref	Expression
dral2.1	|- ( A. x x = y -> ( ph <-> ps ) )

Assertion

Ref	Expression
dral2	|- ( A. x x = y -> ( A. z ph <-> A. z ps ) )

Proof of Theorem dral2

Step	Hyp	Ref	Expression
1		hbae 1654	. 2 |- ( A. x x = y -> A. z A. x x = y )
2		dral2.1	. 2 |- ( A. x x = y -> ( ph <-> ps ) )
3	1, 2	albidh 1415	1 |- ( A. x x = y -> ( A. z ph <-> A. z ps ) )

Syntax hints:   -> wi 4   <-> wb 104   A.wal 1288

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 666  ax-5 1382  ax-7 1383  ax-gen 1384  ax-ie2 1429  ax-8 1441  ax-10 1442  ax-11 1443  ax-i12 1444  ax-4 1446  ax-17 1465  ax-i9 1469  ax-ial 1473

This theorem depends on definitions:  df-bi 116

This theorem is referenced by:  drnf2  1670  equveli  1690  drnfc1  2246  drnfc2  2247