Metamath Proof Explorer


Theorem fh2

Description: Foulis-Holland Theorem. If any 2 pairs in a triple of orthomodular lattice elements commute, the triple is distributive. Second of two parts. Theorem 5 of Kalmbach p. 25. (Contributed by NM, 14-Jun-2006) (New usage is discouraged.)

Ref Expression
Assertion fh2 ACBCCCB𝐶AB𝐶CABC=ABAC

Proof

Step Hyp Ref Expression
1 chincl ACBCABC
2 chincl ACCCACC
3 chjcl ABCACCABACC
4 1 2 3 syl2an ACBCACCCABACC
5 4 anandis ACBCCCABACC
6 chjcl BCCCBCC
7 chincl ACBCCABCC
8 6 7 sylan2 ACBCCCABCC
9 chsh ABCCABCS
10 8 9 syl ACBCCCABCS
11 5 10 jca ACBCCCABACCABCS
12 11 3impb ACBCCCABACCABCS
13 12 adantr ACBCCCB𝐶AB𝐶CABACCABCS
14 ledi ACBCCCABACABC
15 14 adantr ACBCCCB𝐶AB𝐶CABACABC
16 chdmj1 ABCACCABAC=ABAC
17 1 2 16 syl2an ACBCACCCABAC=ABAC
18 chdmm1 ACBCAB=AB
19 18 adantr ACBCACCCAB=AB
20 19 ineq1d ACBCACCCABAC=ABAC
21 17 20 eqtrd ACBCACCCABAC=ABAC
22 21 3impdi ACBCCCABAC=ABAC
23 22 ineq2d ACBCCCABCABAC=ABCABAC
24 23 adantr ACBCCCB𝐶AB𝐶CABCABAC=ABCABAC
25 in4 ABCABAC=AABBCAC
26 cmcm2 ACBCA𝐶BA𝐶B
27 cmcm ACBCA𝐶BB𝐶A
28 choccl BCBC
29 cmbr3 ACBCA𝐶BAAB=AB
30 28 29 sylan2 ACBCA𝐶BAAB=AB
31 26 27 30 3bitr3d ACBCB𝐶AAAB=AB
32 31 biimpa ACBCB𝐶AAAB=AB
33 incom AB=BA
34 32 33 eqtrdi ACBCB𝐶AAAB=BA
35 34 3adantl3 ACBCCCB𝐶AAAB=BA
36 35 adantrr ACBCCCB𝐶AB𝐶CAAB=BA
37 36 ineq1d ACBCCCB𝐶AB𝐶CAABBCAC=BABCAC
38 25 37 eqtrid ACBCCCB𝐶AB𝐶CABCABAC=BABCAC
39 24 38 eqtrd ACBCCCB𝐶AB𝐶CABCABAC=BABCAC
40 in4 BABCAC=BBCAAC
41 39 40 eqtrdi ACBCCCB𝐶AB𝐶CABCABAC=BBCAAC
42 ococ BCB=B
43 42 oveq1d BCBC=BC
44 43 ineq2d BCBBC=BBC
45 44 3ad2ant2 ACBCCCBBC=BBC
46 45 adantr ACBCCCB𝐶AB𝐶CBBC=BBC
47 cmcm3 BCCCB𝐶CB𝐶C
48 cmbr3 BCCCB𝐶CBBC=BC
49 28 48 sylan BCCCB𝐶CBBC=BC
50 47 49 bitrd BCCCB𝐶CBBC=BC
51 50 biimpa BCCCB𝐶CBBC=BC
52 51 3adantl1 ACBCCCB𝐶CBBC=BC
53 52 adantrl ACBCCCB𝐶AB𝐶CBBC=BC
54 46 53 eqtr3d ACBCCCB𝐶AB𝐶CBBC=BC
55 54 ineq1d ACBCCCB𝐶AB𝐶CBBCAAC=BCAAC
56 inass BCAAC=BCAAC
57 in12 CAAC=ACAC
58 inass ACAC=ACAC
59 57 58 eqtr4i CAAC=ACAC
60 chocin ACCACAC=0
61 2 60 syl ACCCACAC=0
62 59 61 eqtrid ACCCCAAC=0
63 62 ineq2d ACCCBCAAC=B0
64 56 63 eqtrid ACCCBCAAC=B0
65 64 3adant2 ACBCCCBCAAC=B0
66 chm0 BCB0=0
67 28 66 syl BCB0=0
68 67 3ad2ant2 ACBCCCB0=0
69 65 68 eqtrd ACBCCCBCAAC=0
70 69 adantr ACBCCCB𝐶AB𝐶CBCAAC=0
71 55 70 eqtrd ACBCCCB𝐶AB𝐶CBBCAAC=0
72 41 71 eqtrd ACBCCCB𝐶AB𝐶CABCABAC=0
73 pjoml ABACCABCSABACABCABCABAC=0ABAC=ABC
74 13 15 72 73 syl12anc ACBCCCB𝐶AB𝐶CABAC=ABC
75 74 eqcomd ACBCCCB𝐶AB𝐶CABC=ABAC