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Theorem ivthinc 13261
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 2165 . . . 4  |-  { w  e.  ( A [,] B
)  |  ( F `
 w )  < 
U }  =  {
w  e.  ( A [,] B )  |  ( F `  w
)  <  U }
11 eqid 2165 . . . 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 13260 . . 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 2679 . . 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 9848 . . . . . . . . . 10  |-  ( c  e.  ( A (,) B )  ->  c  e.  RR )
1615ad2antlr 481 . . . . . . . . 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 8010 . . . . . . . 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 3985 . . . . . . . . 9  |-  ( p  =  c  ->  (
p  <  c  <->  c  <  c ) )
19 simplrl 525 . . . . . . . . 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 5486 . . . . . . . . . . 11  |-  ( w  =  c  ->  ( F `  w )  =  ( F `  c ) )
2120breq1d 3992 . . . . . . . . . 10  |-  ( w  =  c  ->  (
( F `  w
)  <  U  <->  ( F `  c )  <  U
) )
22 ioossicc 9895 . . . . . . . . . . . . 13  |-  ( A (,) B )  C_  ( A [,] B )
2322sseli 3138 . . . . . . . . . . . 12  |-  ( c  e.  ( A (,) B )  ->  c  e.  ( A [,] B
) )
2423adantl 275 . . . . . . . . . . 11  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  c  e.  ( A [,] B ) )
2524ad2antrr 480 . . . . . . . . . 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 109 . . . . . . . . . 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 2884 . . . . . . . . 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 2835 . . . . . . . 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 655 . . . . . . 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 3986 . . . . . . . . 9  |-  ( r  =  c  ->  (
c  <  r  <->  c  <  c ) )
31 simplrr 526 . . . . . . . . 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 3994 . . . . . . . . . 10  |-  ( w  =  c  ->  ( U  <  ( F `  w )  <->  U  <  ( F `  c ) ) )
3324ad2antrr 480 . . . . . . . . . 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 109 . . . . . . . . . 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 2884 . . . . . . . . 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 2835 . . . . . . . 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 655 . . . . . . 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 742 . . . . . . 7  |-  ( -.  ( ( F `  c )  <  U  \/  U  <  ( F `
 c ) )  <-> 
( -.  ( F `
 c )  < 
U  /\  -.  U  <  ( F `  c
) ) )
3929, 37, 38sylanbrc 414 . . . . . 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 5486 . . . . . . . . . 10  |-  ( x  =  c  ->  ( F `  x )  =  ( F `  c ) )
4140eleq1d 2235 . . . . . . . . 9  |-  ( x  =  c  ->  (
( F `  x
)  e.  RR  <->  ( F `  c )  e.  RR ) )
427ralrimiva 2539 . . . . . . . . . 10  |-  ( ph  ->  A. x  e.  ( A [,] B ) ( F `  x
)  e.  RR )
4342adantr 274 . . . . . . . . 9  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  A. x  e.  ( A [,] B
) ( F `  x )  e.  RR )
4441, 43, 24rspcdva 2835 . . . . . . . 8  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  ( F `  c )  e.  RR )
453adantr 274 . . . . . . . 8  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  U  e.  RR )
46 reaplt 8486 . . . . . . . 8  |-  ( ( ( F `  c
)  e.  RR  /\  U  e.  RR )  ->  ( ( F `  c ) #  U  <->  ( ( F `  c )  <  U  \/  U  < 
( F `  c
) ) ) )
4744, 45, 46syl2anc 409 . . . . . . 7  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  ( ( F `  c ) #  U 
<->  ( ( F `  c )  <  U  \/  U  <  ( F `
 c ) ) ) )
4847adantr 274 . . . . . 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 663 . . . . 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 7927 . . . . . . 7  |-  ( (
ph  /\  c  e.  ( A (,) B ) )  ->  ( F `  c )  e.  CC )
5150adantr 274 . . . . . 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 7927 . . . . . . 7  |-  ( ph  ->  U  e.  CC )
5352ad2antrr 480 . . . . . 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 8520 . . . . . 6  |-  ( ( ( F `  c
)  e.  CC  /\  U  e.  CC )  ->  ( ( F `  c )  =  U  <->  -.  ( F `  c
) #  U ) )
5551, 53, 54syl2anc 409 . . . . 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 166 . . . 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 114 . . 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 2568 . 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 103    <-> wb 104    \/ wo 698    = wceq 1343    e. wcel 2136   A.wral 2444   E.wrex 2445   E!wreu 2446   {crab 2448    C_ wss 3116   class class class wbr 3982   ` cfv 5188  (class class class)co 5842   CCcc 7751   RRcr 7752    < clt 7933   # cap 8479   (,)cioo 9824   [,]cicc 9827   -cn->ccncf 13197
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 604  ax-in2 605  ax-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-13 2138  ax-14 2139  ax-ext 2147  ax-coll 4097  ax-sep 4100  ax-nul 4108  ax-pow 4153  ax-pr 4187  ax-un 4411  ax-setind 4514  ax-iinf 4565  ax-cnex 7844  ax-resscn 7845  ax-1cn 7846  ax-1re 7847  ax-icn 7848  ax-addcl 7849  ax-addrcl 7850  ax-mulcl 7851  ax-mulrcl 7852  ax-addcom 7853  ax-mulcom 7854  ax-addass 7855  ax-mulass 7856  ax-distr 7857  ax-i2m1 7858  ax-0lt1 7859  ax-1rid 7860  ax-0id 7861  ax-rnegex 7862  ax-precex 7863  ax-cnre 7864  ax-pre-ltirr 7865  ax-pre-ltwlin 7866  ax-pre-lttrn 7867  ax-pre-apti 7868  ax-pre-ltadd 7869  ax-pre-mulgt0 7870  ax-pre-mulext 7871  ax-arch 7872  ax-caucvg 7873  ax-pre-suploc 7874
This theorem depends on definitions:  df-bi 116  df-dc 825  df-3or 969  df-3an 970  df-tru 1346  df-fal 1349  df-nf 1449  df-sb 1751  df-eu 2017  df-mo 2018  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-ne 2337  df-nel 2432  df-ral 2449  df-rex 2450  df-reu 2451  df-rmo 2452  df-rab 2453  df-v 2728  df-sbc 2952  df-csb 3046  df-dif 3118  df-un 3120  df-in 3122  df-ss 3129  df-nul 3410  df-if 3521  df-pw 3561  df-sn 3582  df-pr 3583  df-op 3585  df-uni 3790  df-int 3825  df-iun 3868  df-br 3983  df-opab 4044  df-mpt 4045  df-tr 4081  df-id 4271  df-po 4274  df-iso 4275  df-iord 4344  df-on 4346  df-ilim 4347  df-suc 4349  df-iom 4568  df-xp 4610  df-rel 4611  df-cnv 4612  df-co 4613  df-dm 4614  df-rn 4615  df-res 4616  df-ima 4617  df-iota 5153  df-fun 5190  df-fn 5191  df-f 5192  df-f1 5193  df-fo 5194  df-f1o 5195  df-fv 5196  df-isom 5197  df-riota 5798  df-ov 5845  df-oprab 5846  df-mpo 5847  df-1st 6108  df-2nd 6109  df-recs 6273  df-frec 6359  df-map 6616  df-sup 6949  df-inf 6950  df-pnf 7935  df-mnf 7936  df-xr 7937  df-ltxr 7938  df-le 7939  df-sub 8071  df-neg 8072  df-reap 8473  df-ap 8480  df-div 8569  df-inn 8858  df-2 8916  df-3 8917  df-4 8918  df-n0 9115  df-z 9192  df-uz 9467  df-rp 9590  df-ioo 9828  df-icc 9831  df-seqfrec 10381  df-exp 10455  df-cj 10784  df-re 10785  df-im 10786  df-rsqrt 10940  df-abs 10941  df-cncf 13198
This theorem is referenced by:  ivthdec  13262  reeff1olem  13332
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