Theorem ltbtwnnqq 7772

Description: There exists a number between any two positive fractions. Proposition 9-2.6(i) of [Gleason] p. 120. (Contributed by Jim Kingdon, 24-Sep-2019.)

Assertion

Ref	Expression
ltbtwnnqq	|- ( A <Q B <-> E. x e. Q. ( A <Q x /\ x <Q B ) )

Distinct variable groups:   x, A   x, B

Proof of Theorem ltbtwnnqq

Dummy variables y z are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		ltrelnq 7722	. . . . 5 |- <Q C_ ( Q. X. Q. )
2	1	brel 4822	. . . 4 |- ( A <Q B -> ( A e. Q. /\ B e. Q. ) )
3	2	simpld 112	. . 3 |- ( A <Q B -> A e. Q. )
4		ltexnqi 7766	. . 3 |- ( A <Q B -> E. y e. Q. ( A +Q y ) = B )
5		nsmallnq 7770	. . . . . 6 |- ( y e. Q. -> E. z z <Q y )
6	1	brel 4822	. . . . . . . . . . . . . . 15 |- ( z <Q y -> ( z e. Q. /\ y e. Q. ) )
7	6	simpld 112	. . . . . . . . . . . . . 14 |- ( z <Q y -> z e. Q. )
8		ltaddnq 7764	. . . . . . . . . . . . . 14 |- ( ( A e. Q. /\ z e. Q. ) -> A <Q ( A +Q z ) )
9	7, 8	sylan2 286	. . . . . . . . . . . . 13 |- ( ( A e. Q. /\ z <Q y ) -> A <Q ( A +Q z ) )
10	9	ancoms 268	. . . . . . . . . . . 12 |- ( ( z <Q y /\ A e. Q. ) -> A <Q ( A +Q z ) )
11	10	adantr 276	. . . . . . . . . . 11 |- ( ( ( z <Q y /\ A e. Q. ) /\ ( A +Q y ) = B ) -> A <Q ( A +Q z ) )
12		ltanqi 7759	. . . . . . . . . . . . 13 |- ( ( z <Q y /\ A e. Q. ) -> ( A +Q z ) <Q ( A +Q y ) )
13	12	adantr 276	. . . . . . . . . . . 12 |- ( ( ( z <Q y /\ A e. Q. ) /\ ( A +Q y ) = B ) -> ( A +Q z ) <Q ( A +Q y ) )
14		breq2 4129	. . . . . . . . . . . . 13 |- ( ( A +Q y ) = B -> ( ( A +Q z ) <Q ( A +Q y ) <-> ( A +Q z ) <Q B ) )
15	14	adantl 277	. . . . . . . . . . . 12 |- ( ( ( z <Q y /\ A e. Q. ) /\ ( A +Q y ) = B ) -> ( ( A +Q z ) <Q ( A +Q y ) <-> ( A +Q z ) <Q B ) )
16	13, 15	mpbid 147	. . . . . . . . . . 11 |- ( ( ( z <Q y /\ A e. Q. ) /\ ( A +Q y ) = B ) -> ( A +Q z ) <Q B )
17		addclnq 7732	. . . . . . . . . . . . . . 15 |- ( ( A e. Q. /\ z e. Q. ) -> ( A +Q z ) e. Q. )
18	7, 17	sylan2 286	. . . . . . . . . . . . . 14 |- ( ( A e. Q. /\ z <Q y ) -> ( A +Q z ) e. Q. )
19	18	ancoms 268	. . . . . . . . . . . . 13 |- ( ( z <Q y /\ A e. Q. ) -> ( A +Q z ) e. Q. )
20	19	adantr 276	. . . . . . . . . . . 12 |- ( ( ( z <Q y /\ A e. Q. ) /\ ( A +Q y ) = B ) -> ( A +Q z ) e. Q. )
21		breq2 4129	. . . . . . . . . . . . . 14 |- ( x = ( A +Q z ) -> ( A <Q x <-> A <Q ( A +Q z ) ) )
22		breq1 4128	. . . . . . . . . . . . . 14 |- ( x = ( A +Q z ) -> ( x <Q B <-> ( A +Q z ) <Q B ) )
23	21, 22	anbi12d 477	. . . . . . . . . . . . 13 |- ( x = ( A +Q z ) -> ( ( A <Q x /\ x <Q B ) <-> ( A <Q ( A +Q z ) /\ ( A +Q z ) <Q B ) ) )
24	23	adantl 277	. . . . . . . . . . . 12 |- ( ( ( ( z <Q y /\ A e. Q. ) /\ ( A +Q y ) = B ) /\ x = ( A +Q z ) ) -> ( ( A <Q x /\ x <Q B ) <-> ( A <Q ( A +Q z ) /\ ( A +Q z ) <Q B ) ) )
25	20, 24	rspcedv 2933	. . . . . . . . . . 11 |- ( ( ( z <Q y /\ A e. Q. ) /\ ( A +Q y ) = B ) -> ( ( A <Q ( A +Q z ) /\ ( A +Q z ) <Q B ) -> E. x e. Q. ( A <Q x /\ x <Q B ) ) )
26	11, 16, 25	mp2and 437	. . . . . . . . . 10 |- ( ( ( z <Q y /\ A e. Q. ) /\ ( A +Q y ) = B ) -> E. x e. Q. ( A <Q x /\ x <Q B ) )
27	26	3impa 1225	. . . . . . . . 9 |- ( ( z <Q y /\ A e. Q. /\ ( A +Q y ) = B ) -> E. x e. Q. ( A <Q x /\ x <Q B ) )
28	27	3coml 1241	. . . . . . . 8 |- ( ( A e. Q. /\ ( A +Q y ) = B /\ z <Q y ) -> E. x e. Q. ( A <Q x /\ x <Q B ) )
29	28	3expia 1236	. . . . . . 7 |- ( ( A e. Q. /\ ( A +Q y ) = B ) -> ( z <Q y -> E. x e. Q. ( A <Q x /\ x <Q B ) ) )
30	29	exlimdv 1872	. . . . . 6 |- ( ( A e. Q. /\ ( A +Q y ) = B ) -> ( E. z z <Q y -> E. x e. Q. ( A <Q x /\ x <Q B ) ) )
31	5, 30	syl5 32	. . . . 5 |- ( ( A e. Q. /\ ( A +Q y ) = B ) -> ( y e. Q. -> E. x e. Q. ( A <Q x /\ x <Q B ) ) )
32	31	impancom 260	. . . 4 |- ( ( A e. Q. /\ y e. Q. ) -> ( ( A +Q y ) = B -> E. x e. Q. ( A <Q x /\ x <Q B ) ) )
33	32	rexlimdva 2668	. . 3 |- ( A e. Q. -> ( E. y e. Q. ( A +Q y ) = B -> E. x e. Q. ( A <Q x /\ x <Q B ) ) )
34	3, 4, 33	sylc 62	. 2 |- ( A <Q B -> E. x e. Q. ( A <Q x /\ x <Q B ) )
35		ltsonq 7755	. . . 4 |- <Q Or Q.
36	35, 1	sotri 5178	. . 3 |- ( ( A <Q x /\ x <Q B ) -> A <Q B )
37	36	rexlimivw 2664	. 2 |- ( E. x e. Q. ( A <Q x /\ x <Q B ) -> A <Q B )
38	34, 37	impbii 126	1 |- ( A <Q B <-> E. x e. Q. ( A <Q x /\ x <Q B ) )

Syntax hints:   /\ wa 104   <-> wb 105   = wceq 1402   E.wex 1545   e. wcel 2209   E.wrex 2529   class class class wbr 4125  (class class class)co 6075   Q.cnq 7637   +Q cplq 7639   <Q cltq 7642

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 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-coll 4241  ax-sep 4244  ax-nul 4254  ax-pow 4306  ax-pr 4341  ax-un 4573  ax-setind 4679  ax-iinf 4730

This theorem depends on definitions:  df-bi 117  df-dc 847  df-3or 1010  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-ral 2533  df-rex 2534  df-reu 2535  df-rab 2537  df-v 2823  df-sbc 3052  df-csb 3148  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-pw 3687  df-sn 3711  df-pr 3712  df-op 3714  df-uni 3931  df-int 3966  df-iun 4009  df-br 4126  df-opab 4188  df-mpt 4189  df-tr 4225  df-eprel 4429  df-id 4433  df-po 4436  df-iso 4437  df-iord 4506  df-on 4508  df-suc 4511  df-iom 4733  df-xp 4775  df-rel 4776  df-cnv 4777  df-co 4778  df-dm 4779  df-rn 4780  df-res 4781  df-ima 4782  df-iota 5332  df-fun 5374  df-fn 5375  df-f 5376  df-f1 5377  df-fo 5378  df-f1o 5379  df-fv 5380  df-ov 6078  df-oprab 6079  df-mpo 6080  df-1st 6364  df-2nd 6365  df-recs 6566  df-irdg 6631  df-1o 6677  df-oadd 6681  df-omul 6682  df-er 6797  df-ec 6799  df-qs 6803  df-ni 7661  df-pli 7662  df-mi 7663  df-lti 7664  df-plpq 7701  df-mpq 7702  df-enq 7704  df-nqqs 7705  df-plqqs 7706  df-mqqs 7707  df-1nqqs 7708  df-rq 7709  df-ltnqqs 7710

This theorem is referenced by:  ltbtwnnq  7773  nqprrnd  7900  appdivnq  7920  ltnqpr  7950  ltnqpri  7951  recexprlemopl  7982  recexprlemopu  7984  cauappcvgprlemopl  8003  cauappcvgprlemopu  8005  cauappcvgprlem2  8017  caucvgprlemopl  8026  caucvgprlemopu  8028  caucvgprlem2  8037  suplocexprlemru  8076  suplocexprlemloc  8078