Step |
Hyp |
Ref |
Expression |
1 |
|
mdslle1.1 |
|- A e. CH |
2 |
|
mdslle1.2 |
|- B e. CH |
3 |
|
mdslle1.3 |
|- C e. CH |
4 |
|
mdslle1.4 |
|- D e. CH |
5 |
|
ssrin |
|- ( C C_ D -> ( C i^i B ) C_ ( D i^i B ) ) |
6 |
3 2
|
chincli |
|- ( C i^i B ) e. CH |
7 |
4 2
|
chincli |
|- ( D i^i B ) e. CH |
8 |
6 7 1
|
chlej1i |
|- ( ( C i^i B ) C_ ( D i^i B ) -> ( ( C i^i B ) vH A ) C_ ( ( D i^i B ) vH A ) ) |
9 |
|
id |
|- ( B MH* A -> B MH* A ) |
10 |
|
ssin |
|- ( ( A C_ C /\ A C_ D ) <-> A C_ ( C i^i D ) ) |
11 |
10
|
bicomi |
|- ( A C_ ( C i^i D ) <-> ( A C_ C /\ A C_ D ) ) |
12 |
11
|
simplbi |
|- ( A C_ ( C i^i D ) -> A C_ C ) |
13 |
1 2
|
chjcli |
|- ( A vH B ) e. CH |
14 |
3 4 13
|
chlubi |
|- ( ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) <-> ( C vH D ) C_ ( A vH B ) ) |
15 |
14
|
bicomi |
|- ( ( C vH D ) C_ ( A vH B ) <-> ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) |
16 |
15
|
simplbi |
|- ( ( C vH D ) C_ ( A vH B ) -> C C_ ( A vH B ) ) |
17 |
1 2 3
|
3pm3.2i |
|- ( A e. CH /\ B e. CH /\ C e. CH ) |
18 |
|
dmdsl3 |
|- ( ( ( A e. CH /\ B e. CH /\ C e. CH ) /\ ( B MH* A /\ A C_ C /\ C C_ ( A vH B ) ) ) -> ( ( C i^i B ) vH A ) = C ) |
19 |
17 18
|
mpan |
|- ( ( B MH* A /\ A C_ C /\ C C_ ( A vH B ) ) -> ( ( C i^i B ) vH A ) = C ) |
20 |
9 12 16 19
|
syl3an |
|- ( ( B MH* A /\ A C_ ( C i^i D ) /\ ( C vH D ) C_ ( A vH B ) ) -> ( ( C i^i B ) vH A ) = C ) |
21 |
11
|
simprbi |
|- ( A C_ ( C i^i D ) -> A C_ D ) |
22 |
15
|
simprbi |
|- ( ( C vH D ) C_ ( A vH B ) -> D C_ ( A vH B ) ) |
23 |
1 2 4
|
3pm3.2i |
|- ( A e. CH /\ B e. CH /\ D e. CH ) |
24 |
|
dmdsl3 |
|- ( ( ( A e. CH /\ B e. CH /\ D e. CH ) /\ ( B MH* A /\ A C_ D /\ D C_ ( A vH B ) ) ) -> ( ( D i^i B ) vH A ) = D ) |
25 |
23 24
|
mpan |
|- ( ( B MH* A /\ A C_ D /\ D C_ ( A vH B ) ) -> ( ( D i^i B ) vH A ) = D ) |
26 |
9 21 22 25
|
syl3an |
|- ( ( B MH* A /\ A C_ ( C i^i D ) /\ ( C vH D ) C_ ( A vH B ) ) -> ( ( D i^i B ) vH A ) = D ) |
27 |
20 26
|
sseq12d |
|- ( ( B MH* A /\ A C_ ( C i^i D ) /\ ( C vH D ) C_ ( A vH B ) ) -> ( ( ( C i^i B ) vH A ) C_ ( ( D i^i B ) vH A ) <-> C C_ D ) ) |
28 |
8 27
|
syl5ib |
|- ( ( B MH* A /\ A C_ ( C i^i D ) /\ ( C vH D ) C_ ( A vH B ) ) -> ( ( C i^i B ) C_ ( D i^i B ) -> C C_ D ) ) |
29 |
5 28
|
impbid2 |
|- ( ( B MH* A /\ A C_ ( C i^i D ) /\ ( C vH D ) C_ ( A vH B ) ) -> ( C C_ D <-> ( C i^i B ) C_ ( D i^i B ) ) ) |