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Theorem ivthreinc 15436
Description: Restating the intermediate value theorem. Given a hypothesis stating the intermediate value theorem (in a strong form which is not provable given our axioms alone), provide a conclusion similar to the theorem as stated in the Metamath Proof Explorer (which is also similar to how we state the theorem for a strictly monotonic function at ivthinc 15434). Being able to have a hypothesis stating the intermediate value theorem will be helpful when it comes time to show that it implies a constructive taboo. This version of the theorem requires that the function  F is continuous on the entire real line, not just  ( A [,] B ) which may be an unnecessary condition but which is sufficient for the way we want to use it. (Contributed by Jim Kingdon, 7-Jul-2025.)
Hypotheses
Ref Expression
ivthreinc.1  |-  ( ph  ->  A  e.  RR )
ivthreinc.2  |-  ( ph  ->  B  e.  RR )
ivthreinc.3  |-  ( ph  ->  U  e.  RR )
ivthreinc.4  |-  ( ph  ->  A  <  B )
ivthreinc.7  |-  ( ph  ->  F  e.  ( RR
-cn-> RR ) )
ivthreinc.9  |-  ( ph  ->  ( ( F `  A )  <  U  /\  U  <  ( F `
 B ) ) )
ivthreinc.i  |-  ( ph  ->  A. f ( f  e.  ( RR -cn-> RR )  ->  A. a  e.  RR  A. b  e.  RR  ( ( a  <  b  /\  (
f `  a )  <  0  /\  0  < 
( f `  b
) )  ->  E. x  e.  RR  ( a  < 
x  /\  x  <  b  /\  ( f `  x )  =  0 ) ) ) )
Assertion
Ref Expression
ivthreinc  |-  ( ph  ->  E. c  e.  ( A (,) B ) ( F `  c
)  =  U )
Distinct variable groups:    A, a, b, x    A, c, x    B, b, x    B, c    F, a, b, f, x    F, c    U, a, b, f, x    U, c    ph, x
Allowed substitution hints:    ph( f, a, b, c)    A( f)    B( f, a)

Proof of Theorem ivthreinc
Dummy variable  r is distinct from all other variables.
StepHypRef Expression
1 ivthreinc.4 . . . 4  |-  ( ph  ->  A  <  B )
2 eqid 2231 . . . . . 6  |-  ( r  e.  RR  |->  ( ( F `  r )  -  U ) )  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )
3 fveq2 5648 . . . . . . 7  |-  ( r  =  A  ->  ( F `  r )  =  ( F `  A ) )
43oveq1d 6043 . . . . . 6  |-  ( r  =  A  ->  (
( F `  r
)  -  U )  =  ( ( F `
 A )  -  U ) )
5 ivthreinc.1 . . . . . 6  |-  ( ph  ->  A  e.  RR )
6 ivthreinc.7 . . . . . . . . 9  |-  ( ph  ->  F  e.  ( RR
-cn-> RR ) )
7 cncff 15368 . . . . . . . . 9  |-  ( F  e.  ( RR -cn-> RR )  ->  F : RR
--> RR )
86, 7syl 14 . . . . . . . 8  |-  ( ph  ->  F : RR --> RR )
98, 5ffvelcdmd 5791 . . . . . . 7  |-  ( ph  ->  ( F `  A
)  e.  RR )
10 ivthreinc.3 . . . . . . 7  |-  ( ph  ->  U  e.  RR )
119, 10resubcld 8603 . . . . . 6  |-  ( ph  ->  ( ( F `  A )  -  U
)  e.  RR )
122, 4, 5, 11fvmptd3 5749 . . . . 5  |-  ( ph  ->  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  A )  =  ( ( F `  A
)  -  U ) )
13 ivthreinc.9 . . . . . . 7  |-  ( ph  ->  ( ( F `  A )  <  U  /\  U  <  ( F `
 B ) ) )
1413simpld 112 . . . . . 6  |-  ( ph  ->  ( F `  A
)  <  U )
159, 10sublt0d 8793 . . . . . 6  |-  ( ph  ->  ( ( ( F `
 A )  -  U )  <  0  <->  ( F `  A )  <  U ) )
1614, 15mpbird 167 . . . . 5  |-  ( ph  ->  ( ( F `  A )  -  U
)  <  0 )
1712, 16eqbrtrd 4115 . . . 4  |-  ( ph  ->  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  A )  <  0
)
1813simprd 114 . . . . . 6  |-  ( ph  ->  U  <  ( F `
 B ) )
19 ivthreinc.2 . . . . . . . 8  |-  ( ph  ->  B  e.  RR )
208, 19ffvelcdmd 5791 . . . . . . 7  |-  ( ph  ->  ( F `  B
)  e.  RR )
2110, 20posdifd 8755 . . . . . 6  |-  ( ph  ->  ( U  <  ( F `  B )  <->  0  <  ( ( F `
 B )  -  U ) ) )
2218, 21mpbid 147 . . . . 5  |-  ( ph  ->  0  <  ( ( F `  B )  -  U ) )
23 fveq2 5648 . . . . . . 7  |-  ( r  =  B  ->  ( F `  r )  =  ( F `  B ) )
2423oveq1d 6043 . . . . . 6  |-  ( r  =  B  ->  (
( F `  r
)  -  U )  =  ( ( F `
 B )  -  U ) )
2520, 10resubcld 8603 . . . . . 6  |-  ( ph  ->  ( ( F `  B )  -  U
)  e.  RR )
262, 24, 19, 25fvmptd3 5749 . . . . 5  |-  ( ph  ->  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  B )  =  ( ( F `  B
)  -  U ) )
2722, 26breqtrrd 4121 . . . 4  |-  ( ph  ->  0  <  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  B ) )
281, 17, 273jca 1204 . . 3  |-  ( ph  ->  ( A  <  B  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  A )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  B ) ) )
29 breq2 4097 . . . . . 6  |-  ( b  =  B  ->  ( A  <  b  <->  A  <  B ) )
30 fveq2 5648 . . . . . . 7  |-  ( b  =  B  ->  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  b
)  =  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  B ) )
3130breq2d 4105 . . . . . 6  |-  ( b  =  B  ->  (
0  <  ( (
r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  b )  <->  0  <  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  B ) ) )
3229, 313anbi13d 1351 . . . . 5  |-  ( b  =  B  ->  (
( A  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  A )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  b ) )  <->  ( A  < 
B  /\  ( (
r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  A )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  B ) ) ) )
33 breq2 4097 . . . . . . 7  |-  ( b  =  B  ->  (
x  <  b  <->  x  <  B ) )
34333anbi2d 1354 . . . . . 6  |-  ( b  =  B  ->  (
( A  <  x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  x )  =  0 )  <->  ( A  < 
x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 x )  =  0 ) ) )
3534rexbidv 2534 . . . . 5  |-  ( b  =  B  ->  ( E. x  e.  RR  ( A  <  x  /\  x  <  b  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  x
)  =  0 )  <->  E. x  e.  RR  ( A  <  x  /\  x  <  B  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  x
)  =  0 ) ) )
3632, 35imbi12d 234 . . . 4  |-  ( b  =  B  ->  (
( ( A  < 
b  /\  ( (
r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  A )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  b ) )  ->  E. x  e.  RR  ( A  <  x  /\  x  <  b  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  x
)  =  0 ) )  <->  ( ( A  <  B  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  A
)  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 B ) )  ->  E. x  e.  RR  ( A  <  x  /\  x  <  B  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  x
)  =  0 ) ) ) )
37 breq1 4096 . . . . . . . 8  |-  ( a  =  A  ->  (
a  <  b  <->  A  <  b ) )
38 fveq2 5648 . . . . . . . . 9  |-  ( a  =  A  ->  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  a
)  =  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  A ) )
3938breq1d 4103 . . . . . . . 8  |-  ( a  =  A  ->  (
( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  a )  <  0  <->  ( ( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  A
)  <  0 ) )
4037, 393anbi12d 1350 . . . . . . 7  |-  ( a  =  A  ->  (
( a  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  a )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  b ) )  <->  ( A  < 
b  /\  ( (
r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  A )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  b ) ) ) )
41 breq1 4096 . . . . . . . . 9  |-  ( a  =  A  ->  (
a  <  x  <->  A  <  x ) )
42413anbi1d 1353 . . . . . . . 8  |-  ( a  =  A  ->  (
( a  <  x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  x )  =  0 )  <->  ( A  < 
x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 x )  =  0 ) ) )
4342rexbidv 2534 . . . . . . 7  |-  ( a  =  A  ->  ( E. x  e.  RR  ( a  <  x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  x )  =  0 )  <->  E. x  e.  RR  ( A  <  x  /\  x  <  b  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  x
)  =  0 ) ) )
4440, 43imbi12d 234 . . . . . 6  |-  ( a  =  A  ->  (
( ( a  < 
b  /\  ( (
r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  a )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  b ) )  ->  E. x  e.  RR  ( a  <  x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  x )  =  0 ) )  <->  ( ( A  <  b  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  A
)  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 b ) )  ->  E. x  e.  RR  ( A  <  x  /\  x  <  b  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  x
)  =  0 ) ) ) )
4544ralbidv 2533 . . . . 5  |-  ( a  =  A  ->  ( A. b  e.  RR  ( ( a  < 
b  /\  ( (
r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  a )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  b ) )  ->  E. x  e.  RR  ( a  <  x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  x )  =  0 ) )  <->  A. b  e.  RR  ( ( A  <  b  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  A
)  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 b ) )  ->  E. x  e.  RR  ( A  <  x  /\  x  <  b  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  x
)  =  0 ) ) ) )
468ffvelcdmda 5790 . . . . . . . . 9  |-  ( (
ph  /\  r  e.  RR )  ->  ( F `
 r )  e.  RR )
4710adantr 276 . . . . . . . . 9  |-  ( (
ph  /\  r  e.  RR )  ->  U  e.  RR )
4846, 47resubcld 8603 . . . . . . . 8  |-  ( (
ph  /\  r  e.  RR )  ->  ( ( F `  r )  -  U )  e.  RR )
4948fmpttd 5810 . . . . . . 7  |-  ( ph  ->  ( r  e.  RR  |->  ( ( F `  r )  -  U
) ) : RR --> RR )
50 ax-resscn 8167 . . . . . . . . 9  |-  RR  C_  CC
5150a1i 9 . . . . . . . 8  |-  ( ph  ->  RR  C_  CC )
528feqmptd 5708 . . . . . . . . . 10  |-  ( ph  ->  F  =  ( r  e.  RR  |->  ( F `
 r ) ) )
53 ssid 3248 . . . . . . . . . . . 12  |-  CC  C_  CC
54 cncfss 15374 . . . . . . . . . . . 12  |-  ( ( RR  C_  CC  /\  CC  C_  CC )  ->  ( RR -cn-> RR )  C_  ( RR -cn-> CC ) )
5550, 53, 54mp2an 426 . . . . . . . . . . 11  |-  ( RR
-cn-> RR )  C_  ( RR -cn-> CC )
5655, 6sselid 3226 . . . . . . . . . 10  |-  ( ph  ->  F  e.  ( RR
-cn-> CC ) )
5752, 56eqeltrrd 2309 . . . . . . . . 9  |-  ( ph  ->  ( r  e.  RR  |->  ( F `  r ) )  e.  ( RR
-cn-> CC ) )
5810recnd 8251 . . . . . . . . . 10  |-  ( ph  ->  U  e.  CC )
5953a1i 9 . . . . . . . . . 10  |-  ( ph  ->  CC  C_  CC )
60 cncfmptc 15387 . . . . . . . . . 10  |-  ( ( U  e.  CC  /\  RR  C_  CC  /\  CC  C_  CC )  ->  (
r  e.  RR  |->  U )  e.  ( RR
-cn-> CC ) )
6158, 51, 59, 60syl3anc 1274 . . . . . . . . 9  |-  ( ph  ->  ( r  e.  RR  |->  U )  e.  ( RR -cn-> CC ) )
6257, 61subcncf 15404 . . . . . . . 8  |-  ( ph  ->  ( r  e.  RR  |->  ( ( F `  r )  -  U
) )  e.  ( RR -cn-> CC ) )
63 cncfcdm 15373 . . . . . . . 8  |-  ( ( RR  C_  CC  /\  (
r  e.  RR  |->  ( ( F `  r
)  -  U ) )  e.  ( RR
-cn-> CC ) )  -> 
( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  e.  ( RR -cn-> RR )  <-> 
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) : RR --> RR ) )
6451, 62, 63syl2anc 411 . . . . . . 7  |-  ( ph  ->  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  e.  ( RR -cn-> RR )  <-> 
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) : RR --> RR ) )
6549, 64mpbird 167 . . . . . 6  |-  ( ph  ->  ( r  e.  RR  |->  ( ( F `  r )  -  U
) )  e.  ( RR -cn-> RR ) )
66 ivthreinc.i . . . . . . 7  |-  ( ph  ->  A. f ( f  e.  ( RR -cn-> RR )  ->  A. a  e.  RR  A. b  e.  RR  ( ( a  <  b  /\  (
f `  a )  <  0  /\  0  < 
( f `  b
) )  ->  E. x  e.  RR  ( a  < 
x  /\  x  <  b  /\  ( f `  x )  =  0 ) ) ) )
67 reex 8209 . . . . . . . . 9  |-  RR  e.  _V
6867mptex 5890 . . . . . . . 8  |-  ( r  e.  RR  |->  ( ( F `  r )  -  U ) )  e.  _V
69 eleq1 2294 . . . . . . . . 9  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( f  e.  ( RR -cn-> RR )  <->  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  e.  ( RR -cn-> RR ) ) )
70 fveq1 5647 . . . . . . . . . . . . . 14  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( f `  a
)  =  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  a ) )
7170breq1d 4103 . . . . . . . . . . . . 13  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( ( f `  a )  <  0  <->  ( ( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  a
)  <  0 ) )
72 fveq1 5647 . . . . . . . . . . . . . 14  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( f `  b
)  =  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  b ) )
7372breq2d 4105 . . . . . . . . . . . . 13  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( 0  <  (
f `  b )  <->  0  <  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 b ) ) )
7471, 733anbi23d 1352 . . . . . . . . . . . 12  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( ( a  < 
b  /\  ( f `  a )  <  0  /\  0  <  ( f `
 b ) )  <-> 
( a  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  a )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  b ) ) ) )
75 fveq1 5647 . . . . . . . . . . . . . . 15  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( f `  x
)  =  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x ) )
7675eqeq1d 2240 . . . . . . . . . . . . . 14  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( ( f `  x )  =  0  <-> 
( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  x )  =  0 ) )
77763anbi3d 1355 . . . . . . . . . . . . 13  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( ( a  < 
x  /\  x  <  b  /\  ( f `  x )  =  0 )  <->  ( a  < 
x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 x )  =  0 ) ) )
7877rexbidv 2534 . . . . . . . . . . . 12  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( E. x  e.  RR  ( a  < 
x  /\  x  <  b  /\  ( f `  x )  =  0 )  <->  E. x  e.  RR  ( a  <  x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  x )  =  0 ) ) )
7974, 78imbi12d 234 . . . . . . . . . . 11  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( ( ( a  <  b  /\  (
f `  a )  <  0  /\  0  < 
( f `  b
) )  ->  E. x  e.  RR  ( a  < 
x  /\  x  <  b  /\  ( f `  x )  =  0 ) )  <->  ( (
a  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  a )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  b ) )  ->  E. x  e.  RR  ( a  < 
x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 x )  =  0 ) ) ) )
8079ralbidv 2533 . . . . . . . . . 10  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( A. b  e.  RR  ( ( a  <  b  /\  (
f `  a )  <  0  /\  0  < 
( f `  b
) )  ->  E. x  e.  RR  ( a  < 
x  /\  x  <  b  /\  ( f `  x )  =  0 ) )  <->  A. b  e.  RR  ( ( a  <  b  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  a
)  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 b ) )  ->  E. x  e.  RR  ( a  <  x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  x )  =  0 ) ) ) )
8180ralbidv 2533 . . . . . . . . 9  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( A. a  e.  RR  A. b  e.  RR  ( ( a  <  b  /\  (
f `  a )  <  0  /\  0  < 
( f `  b
) )  ->  E. x  e.  RR  ( a  < 
x  /\  x  <  b  /\  ( f `  x )  =  0 ) )  <->  A. a  e.  RR  A. b  e.  RR  ( ( a  <  b  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  a
)  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 b ) )  ->  E. x  e.  RR  ( a  <  x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  x )  =  0 ) ) ) )
8269, 81imbi12d 234 . . . . . . . 8  |-  ( f  =  ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  -> 
( ( f  e.  ( RR -cn-> RR )  ->  A. a  e.  RR  A. b  e.  RR  (
( a  <  b  /\  ( f `  a
)  <  0  /\  0  <  ( f `  b ) )  ->  E. x  e.  RR  ( a  <  x  /\  x  <  b  /\  ( f `  x
)  =  0 ) ) )  <->  ( (
r  e.  RR  |->  ( ( F `  r
)  -  U ) )  e.  ( RR
-cn-> RR )  ->  A. a  e.  RR  A. b  e.  RR  ( ( a  <  b  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  a
)  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 b ) )  ->  E. x  e.  RR  ( a  <  x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  x )  =  0 ) ) ) ) )
8368, 82spcv 2901 . . . . . . 7  |-  ( A. f ( f  e.  ( RR -cn-> RR )  ->  A. a  e.  RR  A. b  e.  RR  (
( a  <  b  /\  ( f `  a
)  <  0  /\  0  <  ( f `  b ) )  ->  E. x  e.  RR  ( a  <  x  /\  x  <  b  /\  ( f `  x
)  =  0 ) ) )  ->  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) )  e.  ( RR -cn-> RR )  ->  A. a  e.  RR  A. b  e.  RR  ( ( a  <  b  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  a
)  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 b ) )  ->  E. x  e.  RR  ( a  <  x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  x )  =  0 ) ) ) )
8466, 83syl 14 . . . . . 6  |-  ( ph  ->  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) )  e.  ( RR -cn-> RR )  ->  A. a  e.  RR  A. b  e.  RR  (
( a  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  a )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  b ) )  ->  E. x  e.  RR  ( a  < 
x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 x )  =  0 ) ) ) )
8565, 84mpd 13 . . . . 5  |-  ( ph  ->  A. a  e.  RR  A. b  e.  RR  (
( a  <  b  /\  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  a )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  b ) )  ->  E. x  e.  RR  ( a  < 
x  /\  x  <  b  /\  ( ( r  e.  RR  |->  ( ( F `  r )  -  U ) ) `
 x )  =  0 ) ) )
8645, 85, 5rspcdva 2916 . . . 4  |-  ( ph  ->  A. b  e.  RR  ( ( A  < 
b  /\  ( (
r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  A )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  b ) )  ->  E. x  e.  RR  ( A  <  x  /\  x  <  b  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  x
)  =  0 ) ) )
8736, 86, 19rspcdva 2916 . . 3  |-  ( ph  ->  ( ( A  < 
B  /\  ( (
r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  A )  <  0  /\  0  <  ( ( r  e.  RR  |->  ( ( F `
 r )  -  U ) ) `  B ) )  ->  E. x  e.  RR  ( A  <  x  /\  x  <  B  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  x
)  =  0 ) ) )
8828, 87mpd 13 . 2  |-  ( ph  ->  E. x  e.  RR  ( A  <  x  /\  x  <  B  /\  (
( r  e.  RR  |->  ( ( F `  r )  -  U
) ) `  x
)  =  0 ) )
895adantr 276 . . . . . 6  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  A  e.  RR )
9089rexrd 8272 . . . . 5  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  A  e.  RR* )
9119adantr 276 . . . . . 6  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  B  e.  RR )
9291rexrd 8272 . . . . 5  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  B  e.  RR* )
93 simprl 531 . . . . 5  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  x  e.  RR )
9490, 92, 933jca 1204 . . . 4  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  ( A  e.  RR*  /\  B  e. 
RR*  /\  x  e.  RR ) )
95 simprr1 1072 . . . . 5  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  A  <  x )
96 simprr2 1073 . . . . 5  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  x  <  B )
9795, 96jca 306 . . . 4  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  ( A  <  x  /\  x  < 
B ) )
98 elioo4g 10212 . . . 4  |-  ( x  e.  ( A (,) B )  <->  ( ( A  e.  RR*  /\  B  e.  RR*  /\  x  e.  RR )  /\  ( A  <  x  /\  x  <  B ) ) )
9994, 97, 98sylanbrc 417 . . 3  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  x  e.  ( A (,) B ) )
1008adantr 276 . . . . . 6  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  F : RR
--> RR )
101100, 93ffvelcdmd 5791 . . . . 5  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  ( F `  x )  e.  RR )
102101recnd 8251 . . . 4  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  ( F `  x )  e.  CC )
10358adantr 276 . . . 4  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  U  e.  CC )
104 fveq2 5648 . . . . . . 7  |-  ( r  =  x  ->  ( F `  r )  =  ( F `  x ) )
105104oveq1d 6043 . . . . . 6  |-  ( r  =  x  ->  (
( F `  r
)  -  U )  =  ( ( F `
 x )  -  U ) )
10610adantr 276 . . . . . . 7  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  U  e.  RR )
107101, 106resubcld 8603 . . . . . 6  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  ( ( F `  x )  -  U )  e.  RR )
1082, 105, 93, 107fvmptd3 5749 . . . . 5  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  ( (
r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  ( ( F `
 x )  -  U ) )
109 simprr3 1074 . . . . 5  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  ( (
r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 )
110108, 109eqtr3d 2266 . . . 4  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  ( ( F `  x )  -  U )  =  0 )
111102, 103, 110subeq0d 8541 . . 3  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  ( F `  x )  =  U )
112 fveqeq2 5657 . . . 4  |-  ( c  =  x  ->  (
( F `  c
)  =  U  <->  ( F `  x )  =  U ) )
113112rspcev 2911 . . 3  |-  ( ( x  e.  ( A (,) B )  /\  ( F `  x )  =  U )  ->  E. c  e.  ( A (,) B ) ( F `  c )  =  U )
11499, 111, 113syl2anc 411 . 2  |-  ( (
ph  /\  ( x  e.  RR  /\  ( A  <  x  /\  x  <  B  /\  ( ( r  e.  RR  |->  ( ( F `  r
)  -  U ) ) `  x )  =  0 ) ) )  ->  E. c  e.  ( A (,) B
) ( F `  c )  =  U )
11588, 114rexlimddv 2656 1  |-  ( ph  ->  E. c  e.  ( A (,) B ) ( F `  c
)  =  U )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104    <-> wb 105    /\ w3a 1005   A.wal 1396    = wceq 1398    e. wcel 2202   A.wral 2511   E.wrex 2512    C_ wss 3201   class class class wbr 4093    |-> cmpt 4155   -->wf 5329   ` cfv 5333  (class class class)co 6028   CCcc 8073   RRcr 8074   0cc0 8075   RR*cxr 8256    < clt 8257    - cmin 8393   (,)cioo 10166   -cn->ccncf 15361
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 2204  ax-14 2205  ax-ext 2213  ax-coll 4209  ax-sep 4212  ax-nul 4220  ax-pow 4270  ax-pr 4305  ax-un 4536  ax-setind 4641  ax-iinf 4692  ax-cnex 8166  ax-resscn 8167  ax-1cn 8168  ax-1re 8169  ax-icn 8170  ax-addcl 8171  ax-addrcl 8172  ax-mulcl 8173  ax-mulrcl 8174  ax-addcom 8175  ax-mulcom 8176  ax-addass 8177  ax-mulass 8178  ax-distr 8179  ax-i2m1 8180  ax-0lt1 8181  ax-1rid 8182  ax-0id 8183  ax-rnegex 8184  ax-precex 8185  ax-cnre 8186  ax-pre-ltirr 8187  ax-pre-ltwlin 8188  ax-pre-lttrn 8189  ax-pre-apti 8190  ax-pre-ltadd 8191  ax-pre-mulgt0 8192  ax-pre-mulext 8193  ax-arch 8194  ax-caucvg 8195
This theorem depends on definitions:  df-bi 117  df-stab 839  df-dc 843  df-3or 1006  df-3an 1007  df-tru 1401  df-fal 1404  df-nf 1510  df-sb 1811  df-eu 2082  df-mo 2083  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2364  df-ne 2404  df-nel 2499  df-ral 2516  df-rex 2517  df-reu 2518  df-rmo 2519  df-rab 2520  df-v 2805  df-sbc 3033  df-csb 3129  df-dif 3203  df-un 3205  df-in 3207  df-ss 3214  df-nul 3497  df-if 3608  df-pw 3658  df-sn 3679  df-pr 3680  df-op 3682  df-uni 3899  df-int 3934  df-iun 3977  df-br 4094  df-opab 4156  df-mpt 4157  df-tr 4193  df-id 4396  df-po 4399  df-iso 4400  df-iord 4469  df-on 4471  df-ilim 4472  df-suc 4474  df-iom 4695  df-xp 4737  df-rel 4738  df-cnv 4739  df-co 4740  df-dm 4741  df-rn 4742  df-res 4743  df-ima 4744  df-iota 5293  df-fun 5335  df-fn 5336  df-f 5337  df-f1 5338  df-fo 5339  df-f1o 5340  df-fv 5341  df-isom 5342  df-riota 5981  df-ov 6031  df-oprab 6032  df-mpo 6033  df-1st 6312  df-2nd 6313  df-recs 6514  df-frec 6600  df-map 6862  df-sup 7226  df-inf 7227  df-pnf 8259  df-mnf 8260  df-xr 8261  df-ltxr 8262  df-le 8263  df-sub 8395  df-neg 8396  df-reap 8798  df-ap 8805  df-div 8896  df-inn 9187  df-2 9245  df-3 9246  df-4 9247  df-n0 9446  df-z 9523  df-uz 9799  df-q 9897  df-rp 9932  df-xneg 10050  df-xadd 10051  df-ioo 10170  df-seqfrec 10754  df-exp 10845  df-cj 11463  df-re 11464  df-im 11465  df-rsqrt 11619  df-abs 11620  df-rest 13385  df-topgen 13404  df-psmet 14619  df-xmet 14620  df-met 14621  df-bl 14622  df-mopn 14623  df-top 14789  df-topon 14802  df-bases 14834  df-cn 14979  df-cnp 14980  df-tx 15044  df-cncf 15362
This theorem is referenced by:  ivthdichlem  15442
  Copyright terms: Public domain W3C validator