Theorem exbtwnzlemex 10613

Description: Existence of an integer so that a given real number is between the integer and its successor. The real number must satisfy the n <_ A \/ A < n hypothesis. For example either a rational number or a number which is irrational (in the sense of being apart from any rational number) will meet this condition.

The proof starts by finding two integers which are less than and greater than A. Then this range can be shrunk by choosing an integer in between the endpoints of the range and then deciding which half of the range to keep based on the n <_ A \/ A < n hypothesis, and iterating until the range consists of two consecutive integers. (Contributed by Jim Kingdon, 8-Oct-2021.)

Hypotheses

Ref	Expression
exbtwnzlemex.a	|- ( ph -> A e. RR )
exbtwnzlemex.tri	|- ( ( ph /\ n e. ZZ ) -> ( n <_ A \/ A < n ) )

Assertion

Ref	Expression
exbtwnzlemex	|- ( ph -> E. x e. ZZ ( x <_ A /\ A < ( x + 1 ) ) )

Distinct variable groups:   A, n   x, A   ph, n

Allowed substitution hint:   ph( x)

Proof of Theorem exbtwnzlemex

Dummy variables a j m y are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		exbtwnzlemex.a	. . . 4 |- ( ph -> A e. RR )
2		btwnz 9700	. . . 4 |- ( A e. RR -> ( E. m e. ZZ m < A /\ E. j e. ZZ A < j ) )
3	1, 2	syl 14	. . 3 |- ( ph -> ( E. m e. ZZ m < A /\ E. j e. ZZ A < j ) )
4		reeanv 2715	. . 3 |- ( E. m e. ZZ E. j e. ZZ ( m < A /\ A < j ) <-> ( E. m e. ZZ m < A /\ E. j e. ZZ A < j ) )
5	3, 4	sylibr 134	. 2 |- ( ph -> E. m e. ZZ E. j e. ZZ ( m < A /\ A < j ) )
6		simplrl 537	. . . . . 6 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> m e. ZZ )
7	6	zred 9703	. . . . . . 7 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> m e. RR )
8	1	ad2antrr 488	. . . . . . 7 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> A e. RR )
9		simprl 531	. . . . . . 7 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> m < A )
10	7, 8, 9	ltled 8394	. . . . . 6 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> m <_ A )
11		simprr 533	. . . . . . 7 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> A < j )
12	6	zcnd 9704	. . . . . . . 8 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> m e. CC )
13		simplrr 538	. . . . . . . . 9 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> j e. ZZ )
14	13	zcnd 9704	. . . . . . . 8 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> j e. CC )
15	12, 14	pncan3d 8589	. . . . . . 7 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> ( m + ( j - m ) ) = j )
16	11, 15	breqtrrd 4139	. . . . . 6 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> A < ( m + ( j - m ) ) )
17		breq1 4114	. . . . . . . 8 |- ( y = m -> ( y <_ A <-> m <_ A ) )
18		oveq1 6059	. . . . . . . . 9 |- ( y = m -> ( y + ( j - m ) ) = ( m + ( j - m ) ) )
19	18	breq2d 4123	. . . . . . . 8 |- ( y = m -> ( A < ( y + ( j - m ) ) <-> A < ( m + ( j - m ) ) ) )
20	17, 19	anbi12d 473	. . . . . . 7 |- ( y = m -> ( ( y <_ A /\ A < ( y + ( j - m ) ) ) <-> ( m <_ A /\ A < ( m + ( j - m ) ) ) ) )
21	20	rspcev 2923	. . . . . 6 |- ( ( m e. ZZ /\ ( m <_ A /\ A < ( m + ( j - m ) ) ) ) -> E. y e. ZZ ( y <_ A /\ A < ( y + ( j - m ) ) ) )
22	6, 10, 16, 21	syl12anc 1272	. . . . 5 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> E. y e. ZZ ( y <_ A /\ A < ( y + ( j - m ) ) ) )
23	13	zred 9703	. . . . . . . 8 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> j e. RR )
24	7, 8, 23, 9, 11	lttrd 8401	. . . . . . 7 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> m < j )
25		znnsub 9631	. . . . . . . 8 |- ( ( m e. ZZ /\ j e. ZZ ) -> ( m < j <-> ( j - m ) e. NN ) )
26	25	ad2antlr 489	. . . . . . 7 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> ( m < j <-> ( j - m ) e. NN ) )
27	24, 26	mpbid 147	. . . . . 6 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> ( j - m ) e. NN )
28		exbtwnzlemex.tri	. . . . . . . . . 10 |- ( ( ph /\ n e. ZZ ) -> ( n <_ A \/ A < n ) )
29	28	ralrimiva 2617	. . . . . . . . 9 |- ( ph -> A. n e. ZZ ( n <_ A \/ A < n ) )
30		breq1 4114	. . . . . . . . . . 11 |- ( n = a -> ( n <_ A <-> a <_ A ) )
31		breq2 4115	. . . . . . . . . . 11 |- ( n = a -> ( A < n <-> A < a ) )
32	30, 31	orbi12d 801	. . . . . . . . . 10 |- ( n = a -> ( ( n <_ A \/ A < n ) <-> ( a <_ A \/ A < a ) ) )
33	32	cbvralv 2780	. . . . . . . . 9 |- ( A. n e. ZZ ( n <_ A \/ A < n ) <-> A. a e. ZZ ( a <_ A \/ A < a ) )
34	29, 33	sylib 122	. . . . . . . 8 |- ( ph -> A. a e. ZZ ( a <_ A \/ A < a ) )
35	34	ad2antrr 488	. . . . . . 7 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> A. a e. ZZ ( a <_ A \/ A < a ) )
36	35	r19.21bi 2632	. . . . . 6 |- ( ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) /\ a e. ZZ ) -> ( a <_ A \/ A < a ) )
37	27, 8, 36	exbtwnzlemshrink 10612	. . . . 5 |- ( ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) /\ E. y e. ZZ ( y <_ A /\ A < ( y + ( j - m ) ) ) ) -> E. x e. ZZ ( x <_ A /\ A < ( x + 1 ) ) )
38	22, 37	mpdan 421	. . . 4 |- ( ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) /\ ( m < A /\ A < j ) ) -> E. x e. ZZ ( x <_ A /\ A < ( x + 1 ) ) )
39	38	ex 115	. . 3 |- ( ( ph /\ ( m e. ZZ /\ j e. ZZ ) ) -> ( ( m < A /\ A < j ) -> E. x e. ZZ ( x <_ A /\ A < ( x + 1 ) ) ) )
40	39	rexlimdvva 2670	. 2 |- ( ph -> ( E. m e. ZZ E. j e. ZZ ( m < A /\ A < j ) -> E. x e. ZZ ( x <_ A /\ A < ( x + 1 ) ) ) )
41	5, 40	mpd 13	1 |- ( ph -> E. x e. ZZ ( x <_ A /\ A < ( x + 1 ) ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   \/ wo 716   e. wcel 2205   A.wral 2522   E.wrex 2523   class class class wbr 4111  (class class class)co 6052   RRcr 8128   1c1 8130   + caddc 8132   < clt 8310   <_ cle 8311   - cmin 8446   NNcn 9239   ZZcz 9579

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 2207  ax-14 2208  ax-ext 2216  ax-sep 4230  ax-pow 4289  ax-pr 4324  ax-un 4556  ax-setind 4661  ax-cnex 8220  ax-resscn 8221  ax-1cn 8222  ax-1re 8223  ax-icn 8224  ax-addcl 8225  ax-addrcl 8226  ax-mulcl 8227  ax-addcom 8229  ax-addass 8231  ax-distr 8233  ax-i2m1 8234  ax-0lt1 8235  ax-0id 8237  ax-rnegex 8238  ax-cnre 8240  ax-pre-ltirr 8241  ax-pre-ltwlin 8242  ax-pre-lttrn 8243  ax-pre-ltadd 8245  ax-arch 8248

This theorem depends on definitions:  df-bi 117  df-3or 1006  df-3an 1007  df-tru 1401  df-fal 1404  df-nf 1510  df-sb 1812  df-eu 2085  df-mo 2086  df-clab 2221  df-cleq 2227  df-clel 2230  df-nfc 2375  df-ne 2415  df-nel 2510  df-ral 2527  df-rex 2528  df-reu 2529  df-rab 2531  df-v 2817  df-sbc 3045  df-dif 3215  df-un 3217  df-in 3219  df-ss 3226  df-pw 3673  df-sn 3697  df-pr 3698  df-op 3700  df-uni 3917  df-int 3952  df-br 4112  df-opab 4174  df-id 4416  df-xp 4757  df-rel 4758  df-cnv 4759  df-co 4760  df-dm 4761  df-iota 5314  df-fun 5356  df-fv 5362  df-riota 6005  df-ov 6055  df-oprab 6056  df-mpo 6057  df-pnf 8312  df-mnf 8313  df-xr 8314  df-ltxr 8315  df-le 8316  df-sub 8448  df-neg 8449  df-inn 9240  df-n0 9499  df-z 9580

This theorem is referenced by:  qbtwnz  10615  apbtwnz  10638