Theorem suplocexprlemml 7899

Description: Lemma for suplocexpr 7908. The lower cut of the putative supremum is inhabited. (Contributed by Jim Kingdon, 7-Jan-2024.)

Hypotheses

Ref	Expression
suplocexpr.m	|- ( ph -> E. x x e. A )
suplocexpr.ub	|- ( ph -> E. x e. P. A. y e. A y <P x )
suplocexpr.loc	|- ( ph -> A. x e. P. A. y e. P. ( x <P y -> ( E. z e. A x <P z \/ A. z e. A z <P y ) ) )

Assertion

Ref	Expression
suplocexprlemml	|- ( ph -> E. s e. Q. s e. U. ( 1st " A ) )

Distinct variable groups:   A, s, x, y   ph, s, x, y

Allowed substitution hints:   ph( z)   A( z)

Proof of Theorem suplocexprlemml

Step	Hyp	Ref	Expression
1		suplocexpr.m	. . 3 |- ( ph -> E. x x e. A )
2		suplocexpr.ub	. . . . . . 7 |- ( ph -> E. x e. P. A. y e. A y <P x )
3		suplocexpr.loc	. . . . . . 7 |- ( ph -> A. x e. P. A. y e. P. ( x <P y -> ( E. z e. A x <P z \/ A. z e. A z <P y ) ) )
4	1, 2, 3	suplocexprlemss 7898	. . . . . 6 |- ( ph -> A C_ P. )
5	4	sselda 3224	. . . . 5 |- ( ( ph /\ x e. A ) -> x e. P. )
6		prop 7658	. . . . 5 |- ( x e. P. -> <. ( 1st ` x ) , ( 2nd ` x ) >. e. P. )
7		prml 7660	. . . . 5 |- ( <. ( 1st ` x ) , ( 2nd ` x ) >. e. P. -> E. s e. Q. s e. ( 1st ` x ) )
8	5, 6, 7	3syl 17	. . . 4 |- ( ( ph /\ x e. A ) -> E. s e. Q. s e. ( 1st ` x ) )
9	8	ralrimiva 2603	. . 3 |- ( ph -> A. x e. A E. s e. Q. s e. ( 1st ` x ) )
10		r19.2m 3578	. . 3 |- ( ( E. x x e. A /\ A. x e. A E. s e. Q. s e. ( 1st ` x ) ) -> E. x e. A E. s e. Q. s e. ( 1st ` x ) )
11	1, 9, 10	syl2anc 411	. 2 |- ( ph -> E. x e. A E. s e. Q. s e. ( 1st ` x ) )
12		suplocexprlemell 7896	. . . 4 |- ( s e. U. ( 1st " A ) <-> E. x e. A s e. ( 1st ` x ) )
13	12	rexbii 2537	. . 3 |- ( E. s e. Q. s e. U. ( 1st " A ) <-> E. s e. Q. E. x e. A s e. ( 1st ` x ) )
14		rexcom 2695	. . 3 |- ( E. s e. Q. E. x e. A s e. ( 1st ` x ) <-> E. x e. A E. s e. Q. s e. ( 1st ` x ) )
15	13, 14	bitri 184	. 2 |- ( E. s e. Q. s e. U. ( 1st " A ) <-> E. x e. A E. s e. Q. s e. ( 1st ` x ) )
16	11, 15	sylibr 134	1 |- ( ph -> E. s e. Q. s e. U. ( 1st " A ) )

Syntax hints:   -> wi 4   /\ wa 104   \/ wo 713   E.wex 1538   e. wcel 2200   A.wral 2508   E.wrex 2509   <.cop 3669   U.cuni 3887   class class class wbr 4082   "cima 4721   ` cfv 5317   1stc1st 6282   2ndc2nd 6283   Q.cnq 7463   P.cnp 7474   <P cltp 7478

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-in1 617  ax-in2 618  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-13 2202  ax-14 2203  ax-ext 2211  ax-coll 4198  ax-sep 4201  ax-pow 4257  ax-pr 4292  ax-un 4523  ax-iinf 4679

This theorem depends on definitions:  df-bi 117  df-3an 1004  df-tru 1398  df-nf 1507  df-sb 1809  df-eu 2080  df-mo 2081  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ral 2513  df-rex 2514  df-reu 2515  df-rab 2517  df-v 2801  df-sbc 3029  df-csb 3125  df-dif 3199  df-un 3201  df-in 3203  df-ss 3210  df-pw 3651  df-sn 3672  df-pr 3673  df-op 3675  df-uni 3888  df-int 3923  df-iun 3966  df-br 4083  df-opab 4145  df-mpt 4146  df-id 4383  df-iom 4682  df-xp 4724  df-rel 4725  df-cnv 4726  df-co 4727  df-dm 4728  df-rn 4729  df-res 4730  df-ima 4731  df-iota 5277  df-fun 5319  df-fn 5320  df-f 5321  df-f1 5322  df-fo 5323  df-f1o 5324  df-fv 5325  df-1st 6284  df-2nd 6285  df-qs 6684  df-ni 7487  df-nqqs 7531  df-inp 7649  df-iltp 7653

This theorem is referenced by:  suplocexprlemex  7905