| Step |
Hyp |
Ref |
Expression |
| 1 |
|
ioossioobi.a |
|- ( ph -> A e. RR* ) |
| 2 |
|
ioossioobi.b |
|- ( ph -> B e. RR* ) |
| 3 |
|
ioossioobi.c |
|- ( ph -> C e. RR* ) |
| 4 |
|
ioossioobi.d |
|- ( ph -> D e. RR* ) |
| 5 |
|
ioossioobi.cltd |
|- ( ph -> C < D ) |
| 6 |
|
simpr |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> ( C (,) D ) C_ ( A (,) B ) ) |
| 7 |
|
df-ioo |
|- (,) = ( x e. RR* , y e. RR* |-> { z e. RR* | ( x < z /\ z < y ) } ) |
| 8 |
7
|
ixxssxr |
|- ( A (,) B ) C_ RR* |
| 9 |
|
infxrss |
|- ( ( ( C (,) D ) C_ ( A (,) B ) /\ ( A (,) B ) C_ RR* ) -> inf ( ( A (,) B ) , RR* , < ) <_ inf ( ( C (,) D ) , RR* , < ) ) |
| 10 |
6 8 9
|
sylancl |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> inf ( ( A (,) B ) , RR* , < ) <_ inf ( ( C (,) D ) , RR* , < ) ) |
| 11 |
1
|
adantr |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> A e. RR* ) |
| 12 |
2
|
adantr |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> B e. RR* ) |
| 13 |
|
ioon0 |
|- ( ( C e. RR* /\ D e. RR* ) -> ( ( C (,) D ) =/= (/) <-> C < D ) ) |
| 14 |
3 4 13
|
syl2anc |
|- ( ph -> ( ( C (,) D ) =/= (/) <-> C < D ) ) |
| 15 |
5 14
|
mpbird |
|- ( ph -> ( C (,) D ) =/= (/) ) |
| 16 |
15
|
adantr |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> ( C (,) D ) =/= (/) ) |
| 17 |
|
ssn0 |
|- ( ( ( C (,) D ) C_ ( A (,) B ) /\ ( C (,) D ) =/= (/) ) -> ( A (,) B ) =/= (/) ) |
| 18 |
6 16 17
|
syl2anc |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> ( A (,) B ) =/= (/) ) |
| 19 |
|
idd |
|- ( ( w e. RR* /\ B e. RR* ) -> ( w < B -> w < B ) ) |
| 20 |
|
xrltle |
|- ( ( w e. RR* /\ B e. RR* ) -> ( w < B -> w <_ B ) ) |
| 21 |
|
idd |
|- ( ( A e. RR* /\ w e. RR* ) -> ( A < w -> A < w ) ) |
| 22 |
|
xrltle |
|- ( ( A e. RR* /\ w e. RR* ) -> ( A < w -> A <_ w ) ) |
| 23 |
7 19 20 21 22
|
ixxlb |
|- ( ( A e. RR* /\ B e. RR* /\ ( A (,) B ) =/= (/) ) -> inf ( ( A (,) B ) , RR* , < ) = A ) |
| 24 |
11 12 18 23
|
syl3anc |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> inf ( ( A (,) B ) , RR* , < ) = A ) |
| 25 |
3
|
adantr |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> C e. RR* ) |
| 26 |
4
|
adantr |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> D e. RR* ) |
| 27 |
|
idd |
|- ( ( w e. RR* /\ D e. RR* ) -> ( w < D -> w < D ) ) |
| 28 |
|
xrltle |
|- ( ( w e. RR* /\ D e. RR* ) -> ( w < D -> w <_ D ) ) |
| 29 |
|
idd |
|- ( ( C e. RR* /\ w e. RR* ) -> ( C < w -> C < w ) ) |
| 30 |
|
xrltle |
|- ( ( C e. RR* /\ w e. RR* ) -> ( C < w -> C <_ w ) ) |
| 31 |
7 27 28 29 30
|
ixxlb |
|- ( ( C e. RR* /\ D e. RR* /\ ( C (,) D ) =/= (/) ) -> inf ( ( C (,) D ) , RR* , < ) = C ) |
| 32 |
25 26 16 31
|
syl3anc |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> inf ( ( C (,) D ) , RR* , < ) = C ) |
| 33 |
10 24 32
|
3brtr3d |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> A <_ C ) |
| 34 |
|
supxrss |
|- ( ( ( C (,) D ) C_ ( A (,) B ) /\ ( A (,) B ) C_ RR* ) -> sup ( ( C (,) D ) , RR* , < ) <_ sup ( ( A (,) B ) , RR* , < ) ) |
| 35 |
6 8 34
|
sylancl |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> sup ( ( C (,) D ) , RR* , < ) <_ sup ( ( A (,) B ) , RR* , < ) ) |
| 36 |
7 27 28 29 30
|
ixxub |
|- ( ( C e. RR* /\ D e. RR* /\ ( C (,) D ) =/= (/) ) -> sup ( ( C (,) D ) , RR* , < ) = D ) |
| 37 |
25 26 16 36
|
syl3anc |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> sup ( ( C (,) D ) , RR* , < ) = D ) |
| 38 |
7 19 20 21 22
|
ixxub |
|- ( ( A e. RR* /\ B e. RR* /\ ( A (,) B ) =/= (/) ) -> sup ( ( A (,) B ) , RR* , < ) = B ) |
| 39 |
11 12 18 38
|
syl3anc |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> sup ( ( A (,) B ) , RR* , < ) = B ) |
| 40 |
35 37 39
|
3brtr3d |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> D <_ B ) |
| 41 |
33 40
|
jca |
|- ( ( ph /\ ( C (,) D ) C_ ( A (,) B ) ) -> ( A <_ C /\ D <_ B ) ) |
| 42 |
1
|
adantr |
|- ( ( ph /\ ( A <_ C /\ D <_ B ) ) -> A e. RR* ) |
| 43 |
2
|
adantr |
|- ( ( ph /\ ( A <_ C /\ D <_ B ) ) -> B e. RR* ) |
| 44 |
|
simprl |
|- ( ( ph /\ ( A <_ C /\ D <_ B ) ) -> A <_ C ) |
| 45 |
|
simprr |
|- ( ( ph /\ ( A <_ C /\ D <_ B ) ) -> D <_ B ) |
| 46 |
|
ioossioo |
|- ( ( ( A e. RR* /\ B e. RR* ) /\ ( A <_ C /\ D <_ B ) ) -> ( C (,) D ) C_ ( A (,) B ) ) |
| 47 |
42 43 44 45 46
|
syl22anc |
|- ( ( ph /\ ( A <_ C /\ D <_ B ) ) -> ( C (,) D ) C_ ( A (,) B ) ) |
| 48 |
41 47
|
impbida |
|- ( ph -> ( ( C (,) D ) C_ ( A (,) B ) <-> ( A <_ C /\ D <_ B ) ) ) |