Theorem equsexd 1727

Description: Deduction form of equsex 1726. (Contributed by Jim Kingdon, 29-Dec-2017.)

Hypotheses

Ref	Expression
equsexd.1	|- ( ph -> A. x ph )
equsexd.2	|- ( ph -> ( ch -> A. x ch ) )
equsexd.3	|- ( ph -> ( x = y -> ( ps <-> ch ) ) )

Assertion

Ref	Expression
equsexd	|- ( ph -> ( E. x ( x = y /\ ps ) <-> ch ) )

Proof of Theorem equsexd

Step	Hyp	Ref	Expression
1		equsexd.1	. . 3 |- ( ph -> A. x ph )
2		equsexd.2	. . 3 |- ( ph -> ( ch -> A. x ch ) )
3		equsexd.3	. . . 4 |- ( ph -> ( x = y -> ( ps <-> ch ) ) )
4		biimp 118	. . . . 5 |- ( ( ps <-> ch ) -> ( ps -> ch ) )
5	4	imim2i 12	. . . 4 |- ( ( x = y -> ( ps <-> ch ) ) -> ( x = y -> ( ps -> ch ) ) )
6		pm3.31 262	. . . 4 |- ( ( x = y -> ( ps -> ch ) ) -> ( ( x = y /\ ps ) -> ch ) )
7	3, 5, 6	3syl 17	. . 3 |- ( ph -> ( ( x = y /\ ps ) -> ch ) )
8	1, 2, 7	exlimd2 1593	. 2 |- ( ph -> ( E. x ( x = y /\ ps ) -> ch ) )
9		a9e 1694	. . . 4 |- E. x x = y
10	1	a1i 9	. . . . . . . . 9 |- ( ph -> ( ph -> A. x ph ) )
11	10, 2	jca 306	. . . . . . . 8 |- ( ph -> ( ( ph -> A. x ph ) /\ ( ch -> A. x ch ) ) )
12		anim12 344	. . . . . . . 8 |- ( ( ( ph -> A. x ph ) /\ ( ch -> A. x ch ) ) -> ( ( ph /\ ch ) -> ( A. x ph /\ A. x ch ) ) )
13	11, 12	syl 14	. . . . . . 7 |- ( ph -> ( ( ph /\ ch ) -> ( A. x ph /\ A. x ch ) ) )
14		19.26 1479	. . . . . . 7 |- ( A. x ( ph /\ ch ) <-> ( A. x ph /\ A. x ch ) )
15	13, 14	syl6ibr 162	. . . . . 6 |- ( ph -> ( ( ph /\ ch ) -> A. x ( ph /\ ch ) ) )
16	15	anabsi5 579	. . . . 5 |- ( ( ph /\ ch ) -> A. x ( ph /\ ch ) )
17		idd 21	. . . . . . . 8 |- ( ch -> ( x = y -> x = y ) )
18	17	a1i 9	. . . . . . 7 |- ( ph -> ( ch -> ( x = y -> x = y ) ) )
19	18	imp 124	. . . . . 6 |- ( ( ph /\ ch ) -> ( x = y -> x = y ) )
20		biimpr 130	. . . . . . . . 9 |- ( ( ps <-> ch ) -> ( ch -> ps ) )
21	20	imim2i 12	. . . . . . . 8 |- ( ( x = y -> ( ps <-> ch ) ) -> ( x = y -> ( ch -> ps ) ) )
22		pm2.04 82	. . . . . . . 8 |- ( ( x = y -> ( ch -> ps ) ) -> ( ch -> ( x = y -> ps ) ) )
23	3, 21, 22	3syl 17	. . . . . . 7 |- ( ph -> ( ch -> ( x = y -> ps ) ) )
24	23	imp 124	. . . . . 6 |- ( ( ph /\ ch ) -> ( x = y -> ps ) )
25	19, 24	jcad 307	. . . . 5 |- ( ( ph /\ ch ) -> ( x = y -> ( x = y /\ ps ) ) )
26	16, 25	eximdh 1609	. . . 4 |- ( ( ph /\ ch ) -> ( E. x x = y -> E. x ( x = y /\ ps ) ) )
27	9, 26	mpi 15	. . 3 |- ( ( ph /\ ch ) -> E. x ( x = y /\ ps ) )
28	27	ex 115	. 2 |- ( ph -> ( ch -> E. x ( x = y /\ ps ) ) )
29	8, 28	impbid 129	1 |- ( ph -> ( E. x ( x = y /\ ps ) <-> ch ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   A.wal 1351   = wceq 1353   E.wex 1490

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 1445  ax-gen 1447  ax-ie1 1491  ax-ie2 1492  ax-4 1508  ax-i9 1528  ax-ial 1532

This theorem depends on definitions:  df-bi 117

This theorem is referenced by:  cbvexdh  1924