Theorem euan 1956

Description: Introduction of a conjunct into uniqueness quantifier. (Contributed by NM, 19-Feb-2005.) (Proof shortened by Andrew Salmon, 9-Jul-2011.)

Hypothesis

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

Assertion

Ref	Expression
euan	|- ( E! x ( ph /\ ps ) <-> ( ph /\ E! x ps ) )

Proof of Theorem euan

Step	Hyp	Ref	Expression
1		euan.1	. . . . . 6 |- ( ph -> A. x ph )
2		simpl 102	. . . . . 6 |- ( ( ph /\ ps ) -> ph )
3	1, 2	exlimih 1484	. . . . 5 |- ( E. x ( ph /\ ps ) -> ph )
4	3	adantr 261	. . . 4 |- ( ( E. x ( ph /\ ps ) /\ E* x ( ph /\ ps ) ) -> ph )
5		simpr 103	. . . . . 6 |- ( ( ph /\ ps ) -> ps )
6	5	eximi 1491	. . . . 5 |- ( E. x ( ph /\ ps ) -> E. x ps )
7	6	adantr 261	. . . 4 |- ( ( E. x ( ph /\ ps ) /\ E* x ( ph /\ ps ) ) -> E. x ps )
8		hbe1 1384	. . . . . 6 |- ( E. x ( ph /\ ps ) -> A. x E. x ( ph /\ ps ) )
9	3	a1d 22	. . . . . . . 8 |- ( E. x ( ph /\ ps ) -> ( ps -> ph ) )
10	9	ancrd 309	. . . . . . 7 |- ( E. x ( ph /\ ps ) -> ( ps -> ( ph /\ ps ) ) )
11	5, 10	impbid2 131	. . . . . 6 |- ( E. x ( ph /\ ps ) -> ( ( ph /\ ps ) <-> ps ) )
12	8, 11	mobidh 1934	. . . . 5 |- ( E. x ( ph /\ ps ) -> ( E* x ( ph /\ ps ) <-> E* x ps ) )
13	12	biimpa 280	. . . 4 |- ( ( E. x ( ph /\ ps ) /\ E* x ( ph /\ ps ) ) -> E* x ps )
14	4, 7, 13	jca32 293	. . 3 |- ( ( E. x ( ph /\ ps ) /\ E* x ( ph /\ ps ) ) -> ( ph /\ ( E. x ps /\ E* x ps ) ) )
15		eu5 1947	. . 3 |- ( E! x ( ph /\ ps ) <-> ( E. x ( ph /\ ps ) /\ E* x ( ph /\ ps ) ) )
16		eu5 1947	. . . 4 |- ( E! x ps <-> ( E. x ps /\ E* x ps ) )
17	16	anbi2i 430	. . 3 |- ( ( ph /\ E! x ps ) <-> ( ph /\ ( E. x ps /\ E* x ps ) ) )
18	14, 15, 17	3imtr4i 190	. 2 |- ( E! x ( ph /\ ps ) -> ( ph /\ E! x ps ) )
19		ibar 285	. . . 4 |- ( ph -> ( ps <-> ( ph /\ ps ) ) )
20	1, 19	eubidh 1906	. . 3 |- ( ph -> ( E! x ps <-> E! x ( ph /\ ps ) ) )
21	20	biimpa 280	. 2 |- ( ( ph /\ E! x ps ) -> E! x ( ph /\ ps ) )
22	18, 21	impbii 117	1 |- ( E! x ( ph /\ ps ) <-> ( ph /\ E! x ps ) )

Syntax hints:   -> wi 4   /\ wa 97   <-> wb 98   A.wal 1241   E.wex 1381   E!weu 1900   E*wmo 1901

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428

This theorem depends on definitions:  df-bi 110  df-nf 1350  df-sb 1646  df-eu 1903  df-mo 1904

This theorem is referenced by:  euanv  1957  2eu7  1994