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Mathematics
Mathematics
Problem
If
cos
(
2
sin
−
1
x
)
=
1
9
\cos(2 \sin^{-1} x) = \frac{1}{9}
cos
(
2
sin
−
1
x
)
=
9
1
, then
x
=
x =
x
=
(a) Only
2
/
3
2/3
2/3
(b) Only
−
2
/
3
-2/3
−
2/3
(c)
2
/
3
,
−
2
/
3
2/3, -2/3
2/3
,
−
2/3
(d) Neither
2
/
3
2/3
2/3
nor
−
2
/
3
-2/3
−
2/3
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