试题与答案

函数y=2sin(x-π3),x∈[π2,π],的值域是( ) A.[1,2] B.

题型:选择题

题目:

函数y=2sin(x-
π
3
)
x∈[
π
2
,π]
,的值域是(  )
A.[1,2]B.[-1,
3
]
C.(1,2)D.[1,
3
]

答案:

x∈[

π
2
,π],∴x-
π
3
∈[
π
6
3
]

1
2
≤sin(x-
π
3
)≤1,

即函数y=2sin(x-

π
3
)的值域是[1,2],

故选A.

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