(725°) 
Take Z (110) as equator plane; V,:H=a,=— 60°; 
Pe, 60; 4, = / GOA=— 60°; 4, = ane Oi 2 60? 
y= ~ AB = (111): (111) = — 109°28'17". 
cot a, = — cot a, = — coth, =coth,. 
So according to (3), (5) and (8): 
a = cot? a, (cos y—1) e= cob’ a, sin y 
b = 2 cot a, cosy J = — cot a, (1-+c0s y) 
c= — cota, siny g = cot a, siny 
d = — cot? a, sin y h = cot a, sin +. 
Here is 
1 
tol. a == ee TN e= = 
1 2 
COSY = — ES ; sny = — ej Vy 2. 
so that (9): 
2(a° ee + f?—e’ a, ae z) 2 
BE (eh? —b" En as 
b? + ht ey” + 2 (a° Le? zis eis ij 1 
= par ae ee ae a ee 
2(ae—jfg) + at a ee V2 
(c—h)’? — b? 
== EN > Pees we 
(c—h)?—b? 7 
further is in equation (11): 
nae 2 (prs) = 4 = 4 
1+ 3? rl ve iS 
pr +2g drs? 14 14 
es iat me eG 
2 ( pq—rs) 20 20 
aie eigen 9 
gr? 23 23 
Pom Ne ai 
Consequently we have to solve the equation: 
cos* 20 1 st cos* 20 — ca cos” 20 — - cos 20 — a EA 0) 
‘ : or eet: ET REC 
1 1 
Suppose cos 20 = « — —l=a — ae? then (13) can be changed into: 
eet AOS Mie ane el ths U oeh (14) 
