Theorem iooref1o 15261

Description: A one-to-one mapping from the real numbers onto the open unit interval. (Contributed by Jim Kingdon, 27-Jun-2024.)

Hypothesis

Ref	Expression
iooref1o.f	|- F = ( x e. RR |-> ( 1 / ( 1 + ( exp ` x ) ) ) )

Assertion

Ref	Expression
iooref1o	|- F : RR -1-1-onto-> ( 0 (,) 1 )

Proof of Theorem iooref1o

Dummy variable y is distinct from all other variables.

Step	Hyp	Ref	Expression
1		iooref1o.f	. . 3 |- F = ( x e. RR |-> ( 1 / ( 1 + ( exp ` x ) ) ) )
2		1rp 9689	. . . . . . . . 9 |- 1 e. RR+
3	2	a1i 9	. . . . . . . 8 |- ( x e. RR -> 1 e. RR+ )
4		rpefcl 11728	. . . . . . . 8 |- ( x e. RR -> ( exp ` x ) e. RR+ )
5	3, 4	rpaddcld 9744	. . . . . . 7 |- ( x e. RR -> ( 1 + ( exp ` x ) ) e. RR+ )
6	5	rpreccld 9739	. . . . . 6 |- ( x e. RR -> ( 1 / ( 1 + ( exp ` x ) ) ) e. RR+ )
7	6	rpred 9728	. . . . 5 |- ( x e. RR -> ( 1 / ( 1 + ( exp ` x ) ) ) e. RR )
8	6	rpgt0d 9731	. . . . 5 |- ( x e. RR -> 0 < ( 1 / ( 1 + ( exp ` x ) ) ) )
9		1red 8003	. . . . . . 7 |- ( x e. RR -> 1 e. RR )
10	9, 4	ltaddrpd 9762	. . . . . 6 |- ( x e. RR -> 1 < ( 1 + ( exp ` x ) ) )
11	5	recgt1d 9743	. . . . . 6 |- ( x e. RR -> ( 1 < ( 1 + ( exp ` x ) ) <-> ( 1 / ( 1 + ( exp ` x ) ) ) < 1 ) )
12	10, 11	mpbid 147	. . . . 5 |- ( x e. RR -> ( 1 / ( 1 + ( exp ` x ) ) ) < 1 )
13		0xr 8035	. . . . . 6 |- 0 e. RR*
14		1re 7987	. . . . . . 7 |- 1 e. RR
15	14	rexri 8046	. . . . . 6 |- 1 e. RR*
16		elioo2 9953	. . . . . 6 |- ( ( 0 e. RR* /\ 1 e. RR* ) -> ( ( 1 / ( 1 + ( exp ` x ) ) ) e. ( 0 (,) 1 ) <-> ( ( 1 / ( 1 + ( exp ` x ) ) ) e. RR /\ 0 < ( 1 / ( 1 + ( exp ` x ) ) ) /\ ( 1 / ( 1 + ( exp ` x ) ) ) < 1 ) ) )
17	13, 15, 16	mp2an 426	. . . . 5 |- ( ( 1 / ( 1 + ( exp ` x ) ) ) e. ( 0 (,) 1 ) <-> ( ( 1 / ( 1 + ( exp ` x ) ) ) e. RR /\ 0 < ( 1 / ( 1 + ( exp ` x ) ) ) /\ ( 1 / ( 1 + ( exp ` x ) ) ) < 1 ) )
18	7, 8, 12, 17	syl3anbrc 1183	. . . 4 |- ( x e. RR -> ( 1 / ( 1 + ( exp ` x ) ) ) e. ( 0 (,) 1 ) )
19	18	adantl 277	. . 3 |- ( ( T. /\ x e. RR ) -> ( 1 / ( 1 + ( exp ` x ) ) ) e. ( 0 (,) 1 ) )
20		elioore 9944	. . . . . . . . . 10 |- ( y e. ( 0 (,) 1 ) -> y e. RR )
21		eliooord 9960	. . . . . . . . . . 11 |- ( y e. ( 0 (,) 1 ) -> ( 0 < y /\ y < 1 ) )
22	21	simpld 112	. . . . . . . . . 10 |- ( y e. ( 0 (,) 1 ) -> 0 < y )
23	20, 22	elrpd 9725	. . . . . . . . 9 |- ( y e. ( 0 (,) 1 ) -> y e. RR+ )
24	23	rpreccld 9739	. . . . . . . 8 |- ( y e. ( 0 (,) 1 ) -> ( 1 / y ) e. RR+ )
25	24	rpred 9728	. . . . . . 7 |- ( y e. ( 0 (,) 1 ) -> ( 1 / y ) e. RR )
26		1red 8003	. . . . . . 7 |- ( y e. ( 0 (,) 1 ) -> 1 e. RR )
27	25, 26	resubcld 8369	. . . . . 6 |- ( y e. ( 0 (,) 1 ) -> ( ( 1 / y ) - 1 ) e. RR )
28	21	simprd 114	. . . . . . . 8 |- ( y e. ( 0 (,) 1 ) -> y < 1 )
29	23	reclt1d 9742	. . . . . . . 8 |- ( y e. ( 0 (,) 1 ) -> ( y < 1 <-> 1 < ( 1 / y ) ) )
30	28, 29	mpbid 147	. . . . . . 7 |- ( y e. ( 0 (,) 1 ) -> 1 < ( 1 / y ) )
31	26, 25	posdifd 8520	. . . . . . 7 |- ( y e. ( 0 (,) 1 ) -> ( 1 < ( 1 / y ) <-> 0 < ( ( 1 / y ) - 1 ) ) )
32	30, 31	mpbid 147	. . . . . 6 |- ( y e. ( 0 (,) 1 ) -> 0 < ( ( 1 / y ) - 1 ) )
33	27, 32	elrpd 9725	. . . . 5 |- ( y e. ( 0 (,) 1 ) -> ( ( 1 / y ) - 1 ) e. RR+ )
34	33	relogcld 14780	. . . 4 |- ( y e. ( 0 (,) 1 ) -> ( log ` ( ( 1 / y ) - 1 ) ) e. RR )
35	34	adantl 277	. . 3 |- ( ( T. /\ y e. ( 0 (,) 1 ) ) -> ( log ` ( ( 1 / y ) - 1 ) ) e. RR )
36		1cnd 8004	. . . . . . 7 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> 1 e. CC )
37	4	adantr 276	. . . . . . . . 9 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( exp ` x ) e. RR+ )
38	37	rpcnd 9730	. . . . . . . 8 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( exp ` x ) e. CC )
39	36, 38	addcld 8008	. . . . . . 7 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( 1 + ( exp ` x ) ) e. CC )
40	23	adantl 277	. . . . . . . 8 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> y e. RR+ )
41	40	rpcnd 9730	. . . . . . 7 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> y e. CC )
42	40	rpap0d 9734	. . . . . . 7 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> y # 0 )
43	36, 39, 41, 42	divmulap2d 8812	. . . . . 6 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( ( 1 / y ) = ( 1 + ( exp ` x ) ) <-> 1 = ( y x. ( 1 + ( exp ` x ) ) ) ) )
44	24	adantl 277	. . . . . . . . . 10 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( 1 / y ) e. RR+ )
45	44	rpcnd 9730	. . . . . . . . 9 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( 1 / y ) e. CC )
46	36, 38, 45	addrsub 8359	. . . . . . . 8 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( ( 1 + ( exp ` x ) ) = ( 1 / y ) <-> ( exp ` x ) = ( ( 1 / y ) - 1 ) ) )
47	33	adantl 277	. . . . . . . . . 10 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( ( 1 / y ) - 1 ) e. RR+ )
48	47	reeflogd 14781	. . . . . . . . 9 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( exp ` ( log ` ( ( 1 / y ) - 1 ) ) ) = ( ( 1 / y ) - 1 ) )
49	48	eqeq2d 2201	. . . . . . . 8 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( ( exp ` x ) = ( exp ` ( log ` ( ( 1 / y ) - 1 ) ) ) <-> ( exp ` x ) = ( ( 1 / y ) - 1 ) ) )
50		reef11 11742	. . . . . . . . 9 |- ( ( x e. RR /\ ( log ` ( ( 1 / y ) - 1 ) ) e. RR ) -> ( ( exp ` x ) = ( exp ` ( log ` ( ( 1 / y ) - 1 ) ) ) <-> x = ( log ` ( ( 1 / y ) - 1 ) ) ) )
51	34, 50	sylan2 286	. . . . . . . 8 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( ( exp ` x ) = ( exp ` ( log ` ( ( 1 / y ) - 1 ) ) ) <-> x = ( log ` ( ( 1 / y ) - 1 ) ) ) )
52	46, 49, 51	3bitr2rd 217	. . . . . . 7 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( x = ( log ` ( ( 1 / y ) - 1 ) ) <-> ( 1 + ( exp ` x ) ) = ( 1 / y ) ) )
53		eqcom 2191	. . . . . . 7 |- ( ( 1 + ( exp ` x ) ) = ( 1 / y ) <-> ( 1 / y ) = ( 1 + ( exp ` x ) ) )
54	52, 53	bitrdi 196	. . . . . 6 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( x = ( log ` ( ( 1 / y ) - 1 ) ) <-> ( 1 / y ) = ( 1 + ( exp ` x ) ) ) )
55	5	adantr 276	. . . . . . . 8 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( 1 + ( exp ` x ) ) e. RR+ )
56	55	rpap0d 9734	. . . . . . 7 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( 1 + ( exp ` x ) ) # 0 )
57	36, 41, 39, 56	divmulap3d 8813	. . . . . 6 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( ( 1 / ( 1 + ( exp ` x ) ) ) = y <-> 1 = ( y x. ( 1 + ( exp ` x ) ) ) ) )
58	43, 54, 57	3bitr4d 220	. . . . 5 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( x = ( log ` ( ( 1 / y ) - 1 ) ) <-> ( 1 / ( 1 + ( exp ` x ) ) ) = y ) )
59		eqcom 2191	. . . . 5 |- ( ( 1 / ( 1 + ( exp ` x ) ) ) = y <-> y = ( 1 / ( 1 + ( exp ` x ) ) ) )
60	58, 59	bitrdi 196	. . . 4 |- ( ( x e. RR /\ y e. ( 0 (,) 1 ) ) -> ( x = ( log ` ( ( 1 / y ) - 1 ) ) <-> y = ( 1 / ( 1 + ( exp ` x ) ) ) ) )
61	60	adantl 277	. . 3 |- ( ( T. /\ ( x e. RR /\ y e. ( 0 (,) 1 ) ) ) -> ( x = ( log ` ( ( 1 / y ) - 1 ) ) <-> y = ( 1 / ( 1 + ( exp ` x ) ) ) ) )
62	1, 19, 35, 61	f1o2d 6100	. 2 |- ( T. -> F : RR -1-1-onto-> ( 0 (,) 1 ) )
63	62	mptru 1373	1 |- F : RR -1-1-onto-> ( 0 (,) 1 )

Syntax hints:   /\ wa 104   <-> wb 105   /\ w3a 980   = wceq 1364   T. wtru 1365   e. wcel 2160   class class class wbr 4018   |-> cmpt 4079   -1-1-onto->wf1o 5234   ` cfv 5235  (class class class)co 5897   RRcr 7841   0cc0 7842   1c1 7843   + caddc 7845   x. cmul 7847   RR*cxr 8022   < clt 8023   - cmin 8159   / cdiv 8660   RR+crp 9685   (,)cioo 9920   expce 11685   logclog 14754

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 615  ax-in2 616  ax-io 710  ax-5 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-10 1516  ax-11 1517  ax-i12 1518  ax-bndl 1520  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-13 2162  ax-14 2163  ax-ext 2171  ax-coll 4133  ax-sep 4136  ax-nul 4144  ax-pow 4192  ax-pr 4227  ax-un 4451  ax-setind 4554  ax-iinf 4605  ax-cnex 7933  ax-resscn 7934  ax-1cn 7935  ax-1re 7936  ax-icn 7937  ax-addcl 7938  ax-addrcl 7939  ax-mulcl 7940  ax-mulrcl 7941  ax-addcom 7942  ax-mulcom 7943  ax-addass 7944  ax-mulass 7945  ax-distr 7946  ax-i2m1 7947  ax-0lt1 7948  ax-1rid 7949  ax-0id 7950  ax-rnegex 7951  ax-precex 7952  ax-cnre 7953  ax-pre-ltirr 7954  ax-pre-ltwlin 7955  ax-pre-lttrn 7956  ax-pre-apti 7957  ax-pre-ltadd 7958  ax-pre-mulgt0 7959  ax-pre-mulext 7960  ax-arch 7961  ax-caucvg 7962  ax-pre-suploc 7963  ax-addf 7964  ax-mulf 7965

This theorem depends on definitions:  df-bi 117  df-stab 832  df-dc 836  df-3or 981  df-3an 982  df-tru 1367  df-fal 1370  df-nf 1472  df-sb 1774  df-eu 2041  df-mo 2042  df-clab 2176  df-cleq 2182  df-clel 2185  df-nfc 2321  df-ne 2361  df-nel 2456  df-ral 2473  df-rex 2474  df-reu 2475  df-rmo 2476  df-rab 2477  df-v 2754  df-sbc 2978  df-csb 3073  df-dif 3146  df-un 3148  df-in 3150  df-ss 3157  df-nul 3438  df-if 3550  df-pw 3592  df-sn 3613  df-pr 3614  df-op 3616  df-uni 3825  df-int 3860  df-iun 3903  df-disj 3996  df-br 4019  df-opab 4080  df-mpt 4081  df-tr 4117  df-id 4311  df-po 4314  df-iso 4315  df-iord 4384  df-on 4386  df-ilim 4387  df-suc 4389  df-iom 4608  df-xp 4650  df-rel 4651  df-cnv 4652  df-co 4653  df-dm 4654  df-rn 4655  df-res 4656  df-ima 4657  df-iota 5196  df-fun 5237  df-fn 5238  df-f 5239  df-f1 5240  df-fo 5241  df-f1o 5242  df-fv 5243  df-isom 5244  df-riota 5852  df-ov 5900  df-oprab 5901  df-mpo 5902  df-of 6107  df-1st 6166  df-2nd 6167  df-recs 6331  df-irdg 6396  df-frec 6417  df-1o 6442  df-oadd 6446  df-er 6560  df-map 6677  df-pm 6678  df-en 6768  df-dom 6769  df-fin 6770  df-sup 7014  df-inf 7015  df-pnf 8025  df-mnf 8026  df-xr 8027  df-ltxr 8028  df-le 8029  df-sub 8161  df-neg 8162  df-reap 8563  df-ap 8570  df-div 8661  df-inn 8951  df-2 9009  df-3 9010  df-4 9011  df-n0 9208  df-z 9285  df-uz 9560  df-q 9652  df-rp 9686  df-xneg 9804  df-xadd 9805  df-ioo 9924  df-ico 9926  df-icc 9927  df-fz 10041  df-fzo 10175  df-seqfrec 10479  df-exp 10554  df-fac 10741  df-bc 10763  df-ihash 10791  df-shft 10859  df-cj 10886  df-re 10887  df-im 10888  df-rsqrt 11042  df-abs 11043  df-clim 11322  df-sumdc 11397  df-ef 11691  df-e 11692  df-rest 12749  df-topgen 12768  df-psmet 13873  df-xmet 13874  df-met 13875  df-bl 13876  df-mopn 13877  df-top 13975  df-topon 13988  df-bases 14020  df-ntr 14073  df-cn 14165  df-cnp 14166  df-tx 14230  df-cncf 14535  df-limced 14602  df-dvap 14603  df-relog 14756

This theorem is referenced by:  iooreen  15262