Theorem suplocexprlemml 8031

Description: Lemma for suplocexpr 8040. 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 8030	. . . . . 6 |- ( ph -> A C_ P. )
5	4	sselda 3238	. . . . 5 |- ( ( ph /\ x e. A ) -> x e. P. )
6		prop 7790	. . . . 5 |- ( x e. P. -> <. ( 1st ` x ) , ( 2nd ` x ) >. e. P. )
7		prml 7792	. . . . 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 2615	. . 3 |- ( ph -> A. x e. A E. s e. Q. s e. ( 1st ` x ) )
10		r19.2m 3596	. . 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 8028	. . . 4 |- ( s e. U. ( 1st " A ) <-> E. x e. A s e. ( 1st ` x ) )
13	12	rexbii 2549	. . 3 |- ( E. s e. Q. s e. U. ( 1st " A ) <-> E. s e. Q. E. x e. A s e. ( 1st ` x ) )
14		rexcom 2707	. . 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 716   E.wex 1541   e. wcel 2203   A.wral 2520   E.wrex 2521   <.cop 3692   U.cuni 3914   class class class wbr 4109   "cima 4752   ` cfv 5352   1stc1st 6332   2ndc2nd 6333   Q.cnq 7595   P.cnp 7606   <P cltp 7610

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 619  ax-in2 620  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2205  ax-14 2206  ax-ext 2214  ax-coll 4225  ax-sep 4228  ax-pow 4287  ax-pr 4322  ax-un 4554  ax-iinf 4710

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1812  df-eu 2083  df-mo 2084  df-clab 2219  df-cleq 2225  df-clel 2228  df-nfc 2373  df-ral 2525  df-rex 2526  df-reu 2527  df-rab 2529  df-v 2815  df-sbc 3043  df-csb 3139  df-dif 3213  df-un 3215  df-in 3217  df-ss 3224  df-pw 3671  df-sn 3695  df-pr 3696  df-op 3698  df-uni 3915  df-int 3950  df-iun 3993  df-br 4110  df-opab 4172  df-mpt 4173  df-id 4414  df-iom 4713  df-xp 4755  df-rel 4756  df-cnv 4757  df-co 4758  df-dm 4759  df-rn 4760  df-res 4761  df-ima 4762  df-iota 5312  df-fun 5354  df-fn 5355  df-f 5356  df-f1 5357  df-fo 5358  df-f1o 5359  df-fv 5360  df-1st 6334  df-2nd 6335  df-qs 6773  df-ni 7619  df-nqqs 7663  df-inp 7781  df-iltp 7785

This theorem is referenced by:  suplocexprlemex  8037