Theorem ivthinclemex 12789

Description: Lemma for ivthinc 12790. Existence of a number between the lower cut and the upper cut. (Contributed by Jim Kingdon, 20-Feb-2024.)

Hypotheses

Ref	Expression
ivth.1	|- ( ph -> A e. RR )
ivth.2	|- ( ph -> B e. RR )
ivth.3	|- ( ph -> U e. RR )
ivth.4	|- ( ph -> A < B )
ivth.5	|- ( ph -> ( A [,] B ) C_ D )
ivth.7	|- ( ph -> F e. ( D -cn-> CC ) )
ivth.8	|- ( ( ph /\ x e. ( A [,] B ) ) -> ( F ` x ) e. RR )
ivth.9	|- ( ph -> ( ( F ` A ) < U /\ U < ( F ` B ) ) )
ivthinc.i	|- ( ( ( ph /\ x e. ( A [,] B ) ) /\ ( y e. ( A [,] B ) /\ x < y ) ) -> ( F ` x ) < ( F ` y ) )
ivthinclem.l	|- L = { w e. ( A [,] B ) | ( F ` w ) < U }
ivthinclem.r	|- R = { w e. ( A [,] B ) | U < ( F ` w ) }

Assertion

Ref	Expression
ivthinclemex	|- ( ph -> E! z e. ( A (,) B ) ( A. q e. L q < z /\ A. r e. R z < r ) )

Distinct variable groups:   A, q, r, w   x, A, y, q, r   z, A, q, r   B, q, r, w   x, B, y   z, B   w, F   x, F, y   L, q, r, x, y   z, L   R, q, r, x, y   z, R   w, U   ph, q, r, x, y   ph, z

Allowed substitution hints:   ph( w)   D( x, y, z, w, r, q)   R( w)   U( x, y, z, r, q)   F( z, r, q)   L( w)

Proof of Theorem ivthinclemex

Step	Hyp	Ref	Expression
1		ivth.1	. 2 |- ( ph -> A e. RR )
2		ivth.2	. 2 |- ( ph -> B e. RR )
3		ivthinclem.l	. . . 4 |- L = { w e. ( A [,] B ) | ( F ` w ) < U }
4		ssrab2 3182	. . . 4 |- { w e. ( A [,] B ) | ( F ` w ) < U } C_ ( A [,] B )
5	3, 4	eqsstri 3129	. . 3 |- L C_ ( A [,] B )
6	5	a1i 9	. 2 |- ( ph -> L C_ ( A [,] B ) )
7		ivthinclem.r	. . . 4 |- R = { w e. ( A [,] B ) | U < ( F ` w ) }
8		ssrab2 3182	. . . 4 |- { w e. ( A [,] B ) | U < ( F ` w ) } C_ ( A [,] B )
9	7, 8	eqsstri 3129	. . 3 |- R C_ ( A [,] B )
10	9	a1i 9	. 2 |- ( ph -> R C_ ( A [,] B ) )
11		ivth.3	. . 3 |- ( ph -> U e. RR )
12		ivth.4	. . 3 |- ( ph -> A < B )
13		ivth.5	. . 3 |- ( ph -> ( A [,] B ) C_ D )
14		ivth.7	. . 3 |- ( ph -> F e. ( D -cn-> CC ) )
15		ivth.8	. . 3 |- ( ( ph /\ x e. ( A [,] B ) ) -> ( F ` x ) e. RR )
16		ivth.9	. . 3 |- ( ph -> ( ( F ` A ) < U /\ U < ( F ` B ) ) )
17		ivthinc.i	. . 3 |- ( ( ( ph /\ x e. ( A [,] B ) ) /\ ( y e. ( A [,] B ) /\ x < y ) ) -> ( F ` x ) < ( F ` y ) )
18	1, 2, 11, 12, 13, 14, 15, 16, 17, 3, 7	ivthinclemlm 12781	. 2 |- ( ph -> E. q e. ( A [,] B ) q e. L )
19	1, 2, 11, 12, 13, 14, 15, 16, 17, 3, 7	ivthinclemum 12782	. 2 |- ( ph -> E. r e. ( A [,] B ) r e. R )
20	1, 2, 11, 12, 13, 14, 15, 16, 17, 3, 7	ivthinclemlr 12784	. 2 |- ( ph -> A. q e. ( A [,] B ) ( q e. L <-> E. r e. L q < r ) )
21	1, 2, 11, 12, 13, 14, 15, 16, 17, 3, 7	ivthinclemur 12786	. 2 |- ( ph -> A. r e. ( A [,] B ) ( r e. R <-> E. q e. R q < r ) )
22	1, 2, 11, 12, 13, 14, 15, 16, 17, 3, 7	ivthinclemdisj 12787	. 2 |- ( ph -> ( L i^i R ) = (/) )
23	1, 2, 11, 12, 13, 14, 15, 16, 17, 3, 7	ivthinclemloc 12788	. 2 |- ( ph -> A. q e. ( A [,] B ) A. r e. ( A [,] B ) ( q < r -> ( q e. L \/ r e. R ) ) )
24	1, 2, 6, 10, 18, 19, 20, 21, 22, 23, 12	dedekindicc 12780	1 |- ( ph -> E! z e. ( A (,) B ) ( A. q e. L q < z /\ A. r e. R z < r ) )

Syntax hints:   -> wi 4   /\ wa 103   = wceq 1331   e. wcel 1480   A.wral 2416   E!wreu 2418   {crab 2420   C_ wss 3071   class class class wbr 3929   ` cfv 5123  (class class class)co 5774   CCcc 7618   RRcr 7619   < clt 7800   (,)cioo 9671   [,]cicc 9674   -cn->ccncf 12726

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 603  ax-in2 604  ax-io 698  ax-5 1423  ax-7 1424  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-10 1483  ax-11 1484  ax-i12 1485  ax-bndl 1486  ax-4 1487  ax-13 1491  ax-14 1492  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2121  ax-coll 4043  ax-sep 4046  ax-nul 4054  ax-pow 4098  ax-pr 4131  ax-un 4355  ax-setind 4452  ax-iinf 4502  ax-cnex 7711  ax-resscn 7712  ax-1cn 7713  ax-1re 7714  ax-icn 7715  ax-addcl 7716  ax-addrcl 7717  ax-mulcl 7718  ax-mulrcl 7719  ax-addcom 7720  ax-mulcom 7721  ax-addass 7722  ax-mulass 7723  ax-distr 7724  ax-i2m1 7725  ax-0lt1 7726  ax-1rid 7727  ax-0id 7728  ax-rnegex 7729  ax-precex 7730  ax-cnre 7731  ax-pre-ltirr 7732  ax-pre-ltwlin 7733  ax-pre-lttrn 7734  ax-pre-apti 7735  ax-pre-ltadd 7736  ax-pre-mulgt0 7737  ax-pre-mulext 7738  ax-arch 7739  ax-caucvg 7740  ax-pre-suploc 7741

This theorem depends on definitions:  df-bi 116  df-dc 820  df-3or 963  df-3an 964  df-tru 1334  df-fal 1337  df-nf 1437  df-sb 1736  df-eu 2002  df-mo 2003  df-clab 2126  df-cleq 2132  df-clel 2135  df-nfc 2270  df-ne 2309  df-nel 2404  df-ral 2421  df-rex 2422  df-reu 2423  df-rmo 2424  df-rab 2425  df-v 2688  df-sbc 2910  df-csb 3004  df-dif 3073  df-un 3075  df-in 3077  df-ss 3084  df-nul 3364  df-if 3475  df-pw 3512  df-sn 3533  df-pr 3534  df-op 3536  df-uni 3737  df-int 3772  df-iun 3815  df-br 3930  df-opab 3990  df-mpt 3991  df-tr 4027  df-id 4215  df-po 4218  df-iso 4219  df-iord 4288  df-on 4290  df-ilim 4291  df-suc 4293  df-iom 4505  df-xp 4545  df-rel 4546  df-cnv 4547  df-co 4548  df-dm 4549  df-rn 4550  df-res 4551  df-ima 4552  df-iota 5088  df-fun 5125  df-fn 5126  df-f 5127  df-f1 5128  df-fo 5129  df-f1o 5130  df-fv 5131  df-isom 5132  df-riota 5730  df-ov 5777  df-oprab 5778  df-mpo 5779  df-1st 6038  df-2nd 6039  df-recs 6202  df-frec 6288  df-map 6544  df-sup 6871  df-inf 6872  df-pnf 7802  df-mnf 7803  df-xr 7804  df-ltxr 7805  df-le 7806  df-sub 7935  df-neg 7936  df-reap 8337  df-ap 8344  df-div 8433  df-inn 8721  df-2 8779  df-3 8780  df-4 8781  df-n0 8978  df-z 9055  df-uz 9327  df-rp 9442  df-ioo 9675  df-icc 9678  df-seqfrec 10219  df-exp 10293  df-cj 10614  df-re 10615  df-im 10616  df-rsqrt 10770  df-abs 10771  df-cncf 12727

This theorem is referenced by:  ivthinc  12790