13.07.2007 . 1 f(x)= 2 2cos x − 3a.2cos x + 2a 2 , ) (2 ) (2 ) (2
) ) )
f(x)=0
a=1 f(x)=0
-
? f(x).
-
2 ,
.
1,
1
1
. ) (2
)
2,
J
2
.
) (3
) r
) (2
1,
2
γ OA , = 2sin OB2 2 OB2 .OC2 r : = = R, α β γ OA 4sin sin sin 2 2 2
1
1
J
R OA1 3 = AO 3
)
OC1 = 3 −1. OC
π π , 6
3
π 2
.
.
3 ABCDM a) (3
2ϕ .
)
) (2
)
) (2
)
ABCD, VABCDM = −2h3
,
,
cos 2ϕ 3cos 2 ϕ tg 2ϕ R= h 2
,
cos ϕ =
MN=h
3 .A 7
α α.