| Step |
Hyp |
Ref |
Expression |
| 1 |
|
hlatexch4.j |
|- .\/ = ( join ` K ) |
| 2 |
|
hlatexch4.a |
|- A = ( Atoms ` K ) |
| 3 |
|
simp1 |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> K e. HL ) |
| 4 |
|
simp21 |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> P e. A ) |
| 5 |
|
simp22 |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> Q e. A ) |
| 6 |
|
eqid |
|- ( le ` K ) = ( le ` K ) |
| 7 |
6 1 2
|
hlatlej2 |
|- ( ( K e. HL /\ P e. A /\ Q e. A ) -> Q ( le ` K ) ( P .\/ Q ) ) |
| 8 |
3 4 5 7
|
syl3anc |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> Q ( le ` K ) ( P .\/ Q ) ) |
| 9 |
|
simp23 |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> R e. A ) |
| 10 |
6 1 2
|
hlatlej2 |
|- ( ( K e. HL /\ P e. A /\ R e. A ) -> R ( le ` K ) ( P .\/ R ) ) |
| 11 |
3 4 9 10
|
syl3anc |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> R ( le ` K ) ( P .\/ R ) ) |
| 12 |
|
simp3r |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> ( P .\/ Q ) = ( P .\/ R ) ) |
| 13 |
11 12
|
breqtrrd |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> R ( le ` K ) ( P .\/ Q ) ) |
| 14 |
|
hllat |
|- ( K e. HL -> K e. Lat ) |
| 15 |
14
|
3ad2ant1 |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> K e. Lat ) |
| 16 |
|
eqid |
|- ( Base ` K ) = ( Base ` K ) |
| 17 |
16 2
|
atbase |
|- ( Q e. A -> Q e. ( Base ` K ) ) |
| 18 |
5 17
|
syl |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> Q e. ( Base ` K ) ) |
| 19 |
16 2
|
atbase |
|- ( R e. A -> R e. ( Base ` K ) ) |
| 20 |
9 19
|
syl |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> R e. ( Base ` K ) ) |
| 21 |
16 1 2
|
hlatjcl |
|- ( ( K e. HL /\ P e. A /\ Q e. A ) -> ( P .\/ Q ) e. ( Base ` K ) ) |
| 22 |
3 4 5 21
|
syl3anc |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> ( P .\/ Q ) e. ( Base ` K ) ) |
| 23 |
16 6 1
|
latjle12 |
|- ( ( K e. Lat /\ ( Q e. ( Base ` K ) /\ R e. ( Base ` K ) /\ ( P .\/ Q ) e. ( Base ` K ) ) ) -> ( ( Q ( le ` K ) ( P .\/ Q ) /\ R ( le ` K ) ( P .\/ Q ) ) <-> ( Q .\/ R ) ( le ` K ) ( P .\/ Q ) ) ) |
| 24 |
15 18 20 22 23
|
syl13anc |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> ( ( Q ( le ` K ) ( P .\/ Q ) /\ R ( le ` K ) ( P .\/ Q ) ) <-> ( Q .\/ R ) ( le ` K ) ( P .\/ Q ) ) ) |
| 25 |
8 13 24
|
mpbi2and |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> ( Q .\/ R ) ( le ` K ) ( P .\/ Q ) ) |
| 26 |
|
simp3l |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> Q =/= R ) |
| 27 |
6 1 2
|
ps-1 |
|- ( ( K e. HL /\ ( Q e. A /\ R e. A /\ Q =/= R ) /\ ( P e. A /\ Q e. A ) ) -> ( ( Q .\/ R ) ( le ` K ) ( P .\/ Q ) <-> ( Q .\/ R ) = ( P .\/ Q ) ) ) |
| 28 |
3 5 9 26 4 5 27
|
syl132anc |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> ( ( Q .\/ R ) ( le ` K ) ( P .\/ Q ) <-> ( Q .\/ R ) = ( P .\/ Q ) ) ) |
| 29 |
25 28
|
mpbid |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> ( Q .\/ R ) = ( P .\/ Q ) ) |
| 30 |
29
|
eqcomd |
|- ( ( K e. HL /\ ( P e. A /\ Q e. A /\ R e. A ) /\ ( Q =/= R /\ ( P .\/ Q ) = ( P .\/ R ) ) ) -> ( P .\/ Q ) = ( Q .\/ R ) ) |