| Step |
Hyp |
Ref |
Expression |
| 1 |
|
cdlemeda.l |
|- .<_ = ( le ` K ) |
| 2 |
|
cdlemeda.j |
|- .\/ = ( join ` K ) |
| 3 |
|
cdlemeda.m |
|- ./\ = ( meet ` K ) |
| 4 |
|
cdlemeda.a |
|- A = ( Atoms ` K ) |
| 5 |
|
cdlemeda.h |
|- H = ( LHyp ` K ) |
| 6 |
|
cdlemeda.d |
|- D = ( ( R .\/ S ) ./\ W ) |
| 7 |
|
cdlemednu.u |
|- U = ( ( P .\/ Q ) ./\ W ) |
| 8 |
1 2 3 4 5 6
|
cdlemednpq |
|- ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ Q e. A /\ ( R e. A /\ -. R .<_ W ) ) /\ ( ( S e. A /\ -. S .<_ W ) /\ R .<_ ( P .\/ Q ) /\ -. S .<_ ( P .\/ Q ) ) ) -> -. D .<_ ( P .\/ Q ) ) |
| 9 |
|
simp1l |
|- ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ Q e. A /\ ( R e. A /\ -. R .<_ W ) ) /\ ( ( S e. A /\ -. S .<_ W ) /\ R .<_ ( P .\/ Q ) /\ -. S .<_ ( P .\/ Q ) ) ) -> K e. HL ) |
| 10 |
|
simp1r |
|- ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ Q e. A /\ ( R e. A /\ -. R .<_ W ) ) /\ ( ( S e. A /\ -. S .<_ W ) /\ R .<_ ( P .\/ Q ) /\ -. S .<_ ( P .\/ Q ) ) ) -> W e. H ) |
| 11 |
|
simp21 |
|- ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ Q e. A /\ ( R e. A /\ -. R .<_ W ) ) /\ ( ( S e. A /\ -. S .<_ W ) /\ R .<_ ( P .\/ Q ) /\ -. S .<_ ( P .\/ Q ) ) ) -> P e. A ) |
| 12 |
|
simp22 |
|- ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ Q e. A /\ ( R e. A /\ -. R .<_ W ) ) /\ ( ( S e. A /\ -. S .<_ W ) /\ R .<_ ( P .\/ Q ) /\ -. S .<_ ( P .\/ Q ) ) ) -> Q e. A ) |
| 13 |
1 2 3 4 5 7
|
cdlemeulpq |
|- ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ Q e. A ) ) -> U .<_ ( P .\/ Q ) ) |
| 14 |
9 10 11 12 13
|
syl22anc |
|- ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ Q e. A /\ ( R e. A /\ -. R .<_ W ) ) /\ ( ( S e. A /\ -. S .<_ W ) /\ R .<_ ( P .\/ Q ) /\ -. S .<_ ( P .\/ Q ) ) ) -> U .<_ ( P .\/ Q ) ) |
| 15 |
|
breq1 |
|- ( D = U -> ( D .<_ ( P .\/ Q ) <-> U .<_ ( P .\/ Q ) ) ) |
| 16 |
14 15
|
syl5ibrcom |
|- ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ Q e. A /\ ( R e. A /\ -. R .<_ W ) ) /\ ( ( S e. A /\ -. S .<_ W ) /\ R .<_ ( P .\/ Q ) /\ -. S .<_ ( P .\/ Q ) ) ) -> ( D = U -> D .<_ ( P .\/ Q ) ) ) |
| 17 |
16
|
necon3bd |
|- ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ Q e. A /\ ( R e. A /\ -. R .<_ W ) ) /\ ( ( S e. A /\ -. S .<_ W ) /\ R .<_ ( P .\/ Q ) /\ -. S .<_ ( P .\/ Q ) ) ) -> ( -. D .<_ ( P .\/ Q ) -> D =/= U ) ) |
| 18 |
8 17
|
mpd |
|- ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ Q e. A /\ ( R e. A /\ -. R .<_ W ) ) /\ ( ( S e. A /\ -. S .<_ W ) /\ R .<_ ( P .\/ Q ) /\ -. S .<_ ( P .\/ Q ) ) ) -> D =/= U ) |