. , .
() - - . D l , . D k = n D l,
n - . , . , D l > 2 .
D t = a D (t - t 0)
a - ( a = 0,0000125); t t 0 - . D t , ½ t - t 0½ > 10.
d D d = D cos n
n - . (7.1) D : d = D +Dn,
Dn = d - D = D (cos n - 1) = -2 D sin2 . , 1.
39. : , , . .
. , ( ), a b (. 7.2, ). d MM (. 7.2, ) AB
d = L + f + d,
L - ; f - ; d - .
. 7.2, L = n f / p, p - a b n - , , a b. f / p = K f + d = c,
d = K n + c, (7.2)
K - c - .
f p , K =100, c . d = 100 n.
1/300.
, . n = AB (. 7.3). D n. n 0 = A 0 B 0 = n cos n D = K n 0 + c = K n cosn + c.
.
D cosn, d = K n cos2n + c cos n.
× cos2n,
d = (Kn + ) cos2n + 2 c cosn sin2(n2).
.
d = (Kn + ) cos2n.
, .