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> 已知 a =(2cosx，2sinx)， b =(cosx， 3 cosx)，函数 f(x)= a • b ；（I）求函数f（x）的最小正周期；（II）当 x∈[ π 24 ， 5π 24 ]时，求f（x）的取值范围．

问题：

发布时间：2024-09-10

已知

a

=(2cosx，2sinx)，

b

=(cosx，

3

cosx)，函数 f(x)=

a

•

b

；
（I）求函数f（x）的最小正周期；
（II）当 x∈[

π

24

，

5π

24

]时，求f（x）的取值范围．

参考答案：

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已知 a =(2cosx，2sinx)， b =(cosx， 3 cosx)，函数 f(x)= a • b ； （I）求函数f（x）的最小正周期； （II）当 x∈[ π 24 ， 5π 24 ]时，求f（x）的取值范围．

可能感兴趣的题目：

已知

a

=(2cosx，2sinx)，

b

=(cosx，

3

cosx)，函数 f(x)=

a

•

b

；
（I）求函数f（x）的最小正周期；
（II）当 x∈[

π

24

，

5π

24

]时，求f（x）的取值范围．