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Theorem ivthinc 15086
Description: The intermediate value theorem, increasing case, for a strictly monotonic function. Theorem 5.5 of [Bauer], p. 494. This is Metamath 100 proof #79. (Contributed by Jim Kingdon, 5-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 )
)
Assertion
Ref Expression
ivthinc  |-  ( ph  ->  E. c  e.  ( A (,) B ) ( F `  c
)  =  U )
Distinct variable groups:    A, c, x   
y, A, x    B, c, x    y, B    F, c, x    y, F    U, c, x    y, U    ph, c, x    ph, y
Allowed substitution hints:    D( x, y, c)

Proof of Theorem ivthinc
Dummy variables  p  r  w are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 ivth.1 . . . 4  |-  ( ph  ->  A  e.  RR )
2 ivth.2 . . . 4  |-  ( ph  ->  B  e.  RR )
3 ivth.3 . . . 4  |-  ( ph  ->  U  e.  RR )
4 ivth.4 . . . 4  |-  ( ph  ->  A  <  B )
5 ivth.5 . . . 4  |-  ( ph  ->  ( A [,] B
)  C_  D )
6 ivth.7 . . . 4  |-  ( ph  ->  F  e.  ( D
-cn-> CC ) )
7 ivth.8 . . . 4  |-  ( (
ph  /\  x  e.  ( A [,] B ) )  ->  ( F `  x )  e.  RR )
8 ivth.9 . . . 4  |-  ( ph  ->  ( ( F `  A )  <  U  /\  U  <  ( F `
 B ) ) )
9 ivthinc.i . . . 4  |-  ( ( ( ph  /\  x  e.  ( A [,] B
) )  /\  (
y  e.  ( A [,] B )  /\  x  <  y ) )  ->  ( F `  x )  <  ( F `  y )
)
10 eqid 2204 . . . 4  |-  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U }  =  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
11 eqid 2204 . . . 4  |-  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) }  =  {
w  e.  ( A [,] B )  |  U  <  ( F `
 w ) }
121, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11ivthinclemex 15085 . . 3  |-  ( ph  ->  E! c  e.  ( A (,) B ) ( A. p  e. 
{ w  e.  ( A [,] B )  |  ( F `  w )  <  U } p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )
13 reurex 2723 . . 3  |-  ( E! c  e.  ( A (,) B ) ( A. p  e.  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r )  ->  E. c  e.  ( A (,) B
) ( A. p  e.  { w  e.  ( A [,] B )  |  ( F `  w )  <  U } p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )
1412, 13syl 14 . 2  |-  ( ph  ->  E. c  e.  ( A (,) B ) ( A. p  e. 
{ w  e.  ( A [,] B )  |  ( F `  w )  <  U } p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )
15 elioore 10033 . . . . . . . . . 10  |-  ( c  e.  ( A (,) B )  ->  c  e.  RR )
1615ad2antlr 489 . . . . . . . . 9  |-  ( ( ( ph  /\  c  e.  ( A (,) B
) )  /\  ( A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c  /\  A. r  e.  { w  e.  ( A [,] B )  |  U  <  ( F `  w ) } c  <  r
) )  ->  c  e.  RR )
1716ltnrd 8183 . . . . . . . 8  |-  ( ( ( ph  /\  c  e.  ( A (,) B
) )  /\  ( A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c  /\  A. r  e.  { w  e.  ( A [,] B )  |  U  <  ( F `  w ) } c  <  r
) )  ->  -.  c  <  c )
18 breq1 4046 . . . . . . . . 9  |-  ( p  =  c  ->  (
p  <  c  <->  c  <  c ) )
19 simplrl 535 . . . . . . . . 9  |-  ( ( ( ( ph  /\  c  e.  ( A (,) B ) )  /\  ( A. p  e.  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )  /\  ( F `  c )  <  U )  ->  A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c )
20 fveq2 5575 . . . . . . . . . . 11  |-  ( w  =  c  ->  ( F `  w )  =  ( F `  c ) )
2120breq1d 4053 . . . . . . . . . 10  |-  ( w  =  c  ->  (
( F `  w
)  <  U  <->  ( F `  c )  <  U
) )
22 ioossicc 10080 . . . . . . . . . . . . 13  |-  ( A (,) B )  C_  ( A [,] B )
2322sseli 3188 . . . . . . . . . . . 12  |-  ( c  e.  ( A (,) B )  ->  c  e.  ( A [,] B
) )
2423adantl 277 . . . . . . . . . . 11  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  c  e.  ( A [,] B ) )
2524ad2antrr 488 . . . . . . . . . 10  |-  ( ( ( ( ph  /\  c  e.  ( A (,) B ) )  /\  ( A. p  e.  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )  /\  ( F `  c )  <  U )  -> 
c  e.  ( A [,] B ) )
26 simpr 110 . . . . . . . . . 10  |-  ( ( ( ( ph  /\  c  e.  ( A (,) B ) )  /\  ( A. p  e.  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )  /\  ( F `  c )  <  U )  -> 
( F `  c
)  <  U )
2721, 25, 26elrabd 2930 . . . . . . . . 9  |-  ( ( ( ( ph  /\  c  e.  ( A (,) B ) )  /\  ( A. p  e.  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )  /\  ( F `  c )  <  U )  -> 
c  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } )
2818, 19, 27rspcdva 2881 . . . . . . . 8  |-  ( ( ( ( ph  /\  c  e.  ( A (,) B ) )  /\  ( A. p  e.  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )  /\  ( F `  c )  <  U )  -> 
c  <  c )
2917, 28mtand 666 . . . . . . 7  |-  ( ( ( ph  /\  c  e.  ( A (,) B
) )  /\  ( A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c  /\  A. r  e.  { w  e.  ( A [,] B )  |  U  <  ( F `  w ) } c  <  r
) )  ->  -.  ( F `  c )  <  U )
30 breq2 4047 . . . . . . . . 9  |-  ( r  =  c  ->  (
c  <  r  <->  c  <  c ) )
31 simplrr 536 . . . . . . . . 9  |-  ( ( ( ( ph  /\  c  e.  ( A (,) B ) )  /\  ( A. p  e.  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )  /\  U  <  ( F `  c ) )  ->  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r )
3220breq2d 4055 . . . . . . . . . 10  |-  ( w  =  c  ->  ( U  <  ( F `  w )  <->  U  <  ( F `  c ) ) )
3324ad2antrr 488 . . . . . . . . . 10  |-  ( ( ( ( ph  /\  c  e.  ( A (,) B ) )  /\  ( A. p  e.  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )  /\  U  <  ( F `  c ) )  -> 
c  e.  ( A [,] B ) )
34 simpr 110 . . . . . . . . . 10  |-  ( ( ( ( ph  /\  c  e.  ( A (,) B ) )  /\  ( A. p  e.  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )  /\  U  <  ( F `  c ) )  ->  U  <  ( F `  c ) )
3532, 33, 34elrabd 2930 . . . . . . . . 9  |-  ( ( ( ( ph  /\  c  e.  ( A (,) B ) )  /\  ( A. p  e.  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )  /\  U  <  ( F `  c ) )  -> 
c  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } )
3630, 31, 35rspcdva 2881 . . . . . . . 8  |-  ( ( ( ( ph  /\  c  e.  ( A (,) B ) )  /\  ( A. p  e.  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r ) )  /\  U  <  ( F `  c ) )  -> 
c  <  c )
3717, 36mtand 666 . . . . . . 7  |-  ( ( ( ph  /\  c  e.  ( A (,) B
) )  /\  ( A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c  /\  A. r  e.  { w  e.  ( A [,] B )  |  U  <  ( F `  w ) } c  <  r
) )  ->  -.  U  <  ( F `  c ) )
38 ioran 753 . . . . . . 7  |-  ( -.  ( ( F `  c )  <  U  \/  U  <  ( F `
 c ) )  <-> 
( -.  ( F `
 c )  < 
U  /\  -.  U  <  ( F `  c
) ) )
3929, 37, 38sylanbrc 417 . . . . . 6  |-  ( ( ( ph  /\  c  e.  ( A (,) B
) )  /\  ( A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c  /\  A. r  e.  { w  e.  ( A [,] B )  |  U  <  ( F `  w ) } c  <  r
) )  ->  -.  ( ( F `  c )  <  U  \/  U  <  ( F `
 c ) ) )
40 fveq2 5575 . . . . . . . . . 10  |-  ( x  =  c  ->  ( F `  x )  =  ( F `  c ) )
4140eleq1d 2273 . . . . . . . . 9  |-  ( x  =  c  ->  (
( F `  x
)  e.  RR  <->  ( F `  c )  e.  RR ) )
427ralrimiva 2578 . . . . . . . . . 10  |-  ( ph  ->  A. x  e.  ( A [,] B ) ( F `  x
)  e.  RR )
4342adantr 276 . . . . . . . . 9  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  A. x  e.  ( A [,] B
) ( F `  x )  e.  RR )
4441, 43, 24rspcdva 2881 . . . . . . . 8  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  ( F `  c )  e.  RR )
453adantr 276 . . . . . . . 8  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  U  e.  RR )
46 reaplt 8660 . . . . . . . 8  |-  ( ( ( F `  c
)  e.  RR  /\  U  e.  RR )  ->  ( ( F `  c ) #  U  <->  ( ( F `  c )  <  U  \/  U  < 
( F `  c
) ) ) )
4744, 45, 46syl2anc 411 . . . . . . 7  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  ( ( F `  c ) #  U 
<->  ( ( F `  c )  <  U  \/  U  <  ( F `
 c ) ) ) )
4847adantr 276 . . . . . 6  |-  ( ( ( ph  /\  c  e.  ( A (,) B
) )  /\  ( A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c  /\  A. r  e.  { w  e.  ( A [,] B )  |  U  <  ( F `  w ) } c  <  r
) )  ->  (
( F `  c
) #  U  <->  ( ( F `  c )  <  U  \/  U  < 
( F `  c
) ) ) )
4939, 48mtbird 674 . . . . 5  |-  ( ( ( ph  /\  c  e.  ( A (,) B
) )  /\  ( A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c  /\  A. r  e.  { w  e.  ( A [,] B )  |  U  <  ( F `  w ) } c  <  r
) )  ->  -.  ( F `  c ) #  U )
5044recnd 8100 . . . . . . 7  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  ( F `  c )  e.  CC )
5150adantr 276 . . . . . 6  |-  ( ( ( ph  /\  c  e.  ( A (,) B
) )  /\  ( A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c  /\  A. r  e.  { w  e.  ( A [,] B )  |  U  <  ( F `  w ) } c  <  r
) )  ->  ( F `  c )  e.  CC )
523recnd 8100 . . . . . . 7  |-  ( ph  ->  U  e.  CC )
5352ad2antrr 488 . . . . . 6  |-  ( ( ( ph  /\  c  e.  ( A (,) B
) )  /\  ( A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c  /\  A. r  e.  { w  e.  ( A [,] B )  |  U  <  ( F `  w ) } c  <  r
) )  ->  U  e.  CC )
54 apti 8694 . . . . . 6  |-  ( ( ( F `  c
)  e.  CC  /\  U  e.  CC )  ->  ( ( F `  c )  =  U  <->  -.  ( F `  c
) #  U ) )
5551, 53, 54syl2anc 411 . . . . 5  |-  ( ( ( ph  /\  c  e.  ( A (,) B
) )  /\  ( A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c  /\  A. r  e.  { w  e.  ( A [,] B )  |  U  <  ( F `  w ) } c  <  r
) )  ->  (
( F `  c
)  =  U  <->  -.  ( F `  c ) #  U ) )
5649, 55mpbird 167 . . . 4  |-  ( ( ( ph  /\  c  e.  ( A (,) B
) )  /\  ( A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c  /\  A. r  e.  { w  e.  ( A [,] B )  |  U  <  ( F `  w ) } c  <  r
) )  ->  ( F `  c )  =  U )
5756ex 115 . . 3  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  ( ( A. p  e.  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U } p  < 
c  /\  A. r  e.  { w  e.  ( A [,] B )  |  U  <  ( F `  w ) } c  <  r
)  ->  ( F `  c )  =  U ) )
5857reximdva 2607 . 2  |-  ( ph  ->  ( E. c  e.  ( A (,) B
) ( A. p  e.  { w  e.  ( A [,] B )  |  ( F `  w )  <  U } p  <  c  /\  A. r  e.  { w  e.  ( A [,] B
)  |  U  < 
( F `  w
) } c  < 
r )  ->  E. c  e.  ( A (,) B
) ( F `  c )  =  U ) )
5914, 58mpd 13 1  |-  ( ph  ->  E. c  e.  ( A (,) B ) ( F `  c
)  =  U )
Colors of variables: wff set class
Syntax hints:   -. wn 3    -> wi 4    /\ wa 104    <-> wb 105    \/ wo 709    = wceq 1372    e. wcel 2175   A.wral 2483   E.wrex 2484   E!wreu 2485   {crab 2487    C_ wss 3165   class class class wbr 4043   ` cfv 5270  (class class class)co 5943   CCcc 7922   RRcr 7923    < clt 8106   # cap 8653   (,)cioo 10009   [,]cicc 10012   -cn->ccncf 15013
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 1469  ax-7 1470  ax-gen 1471  ax-ie1 1515  ax-ie2 1516  ax-8 1526  ax-10 1527  ax-11 1528  ax-i12 1529  ax-bndl 1531  ax-4 1532  ax-17 1548  ax-i9 1552  ax-ial 1556  ax-i5r 1557  ax-13 2177  ax-14 2178  ax-ext 2186  ax-coll 4158  ax-sep 4161  ax-nul 4169  ax-pow 4217  ax-pr 4252  ax-un 4479  ax-setind 4584  ax-iinf 4635  ax-cnex 8015  ax-resscn 8016  ax-1cn 8017  ax-1re 8018  ax-icn 8019  ax-addcl 8020  ax-addrcl 8021  ax-mulcl 8022  ax-mulrcl 8023  ax-addcom 8024  ax-mulcom 8025  ax-addass 8026  ax-mulass 8027  ax-distr 8028  ax-i2m1 8029  ax-0lt1 8030  ax-1rid 8031  ax-0id 8032  ax-rnegex 8033  ax-precex 8034  ax-cnre 8035  ax-pre-ltirr 8036  ax-pre-ltwlin 8037  ax-pre-lttrn 8038  ax-pre-apti 8039  ax-pre-ltadd 8040  ax-pre-mulgt0 8041  ax-pre-mulext 8042  ax-arch 8043  ax-caucvg 8044  ax-pre-suploc 8045
This theorem depends on definitions:  df-bi 117  df-dc 836  df-3or 981  df-3an 982  df-tru 1375  df-fal 1378  df-nf 1483  df-sb 1785  df-eu 2056  df-mo 2057  df-clab 2191  df-cleq 2197  df-clel 2200  df-nfc 2336  df-ne 2376  df-nel 2471  df-ral 2488  df-rex 2489  df-reu 2490  df-rmo 2491  df-rab 2492  df-v 2773  df-sbc 2998  df-csb 3093  df-dif 3167  df-un 3169  df-in 3171  df-ss 3178  df-nul 3460  df-if 3571  df-pw 3617  df-sn 3638  df-pr 3639  df-op 3641  df-uni 3850  df-int 3885  df-iun 3928  df-br 4044  df-opab 4105  df-mpt 4106  df-tr 4142  df-id 4339  df-po 4342  df-iso 4343  df-iord 4412  df-on 4414  df-ilim 4415  df-suc 4417  df-iom 4638  df-xp 4680  df-rel 4681  df-cnv 4682  df-co 4683  df-dm 4684  df-rn 4685  df-res 4686  df-ima 4687  df-iota 5231  df-fun 5272  df-fn 5273  df-f 5274  df-f1 5275  df-fo 5276  df-f1o 5277  df-fv 5278  df-isom 5279  df-riota 5898  df-ov 5946  df-oprab 5947  df-mpo 5948  df-1st 6225  df-2nd 6226  df-recs 6390  df-frec 6476  df-map 6736  df-sup 7085  df-inf 7086  df-pnf 8108  df-mnf 8109  df-xr 8110  df-ltxr 8111  df-le 8112  df-sub 8244  df-neg 8245  df-reap 8647  df-ap 8654  df-div 8745  df-inn 9036  df-2 9094  df-3 9095  df-4 9096  df-n0 9295  df-z 9372  df-uz 9648  df-rp 9775  df-ioo 10013  df-icc 10016  df-seqfrec 10591  df-exp 10682  df-cj 11124  df-re 11125  df-im 11126  df-rsqrt 11280  df-abs 11281  df-cncf 15014
This theorem is referenced by:  ivthdec  15087  reeff1olem  15214
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