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Mathematics
Mathematics
Problem
If
cos
α
,
cos
β
\cos \alpha, \cos \beta
cos
α
,
cos
β
and
cos
γ
\cos \gamma
cos
γ
are the roots of the equation
9
x
3
−
9
x
2
−
x
+
1
=
0
9x^3 - 9x^2 - x + 1 = 0
9
x
3
−
9
x
2
−
x
+
1
=
0
,
α
,
β
,
γ
∈
[
0
,
π
]
\alpha, \beta, \gamma \in [0, \pi]
α
,
β
,
γ
∈
[
0
,
π
]
then the radius of the circle whose centre is
(
Σ
α
,
Σ
cos
α
)
(\Sigma \alpha, \Sigma \cos \alpha)
(
Σ
α
,
Σ
cos
α
)
and passing through
(
2
sin
−
1
(
tan
π
/
4
)
,
4
)
(2 \sin^{-1}(\tan \pi/4), 4)
(
2
sin
−
1
(
tan
π
/4
)
,
4
)
is: (a) 2 (b) 3 (c) 4 (d) 5
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