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任意角三角函数的概念

> 已知向量 a =（cosx，2cosx），向量 b =（2cosx，sin（π-x）），若f（x）= a • b +1．（I）求函数f（x）的解析式和最小正周期；（II）若 x∈[0， π 2 ]，求f（x）的最大值和最小值．

问题：

发布时间：2024-09-13

已知向量

a

=（cosx，2cosx），向量

b

=（2cosx，sin（π-x）），若f（x）=

a

•

b

+1．
（I）求函数f（x）的解析式和最小正周期；
（II）若 x∈[0，

π

2

]，求f（x）的最大值和最小值．

参考答案：

提问用户：n4***xNf

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已知向量 a =（cosx，2cosx），向量 b =（2cosx，sin（π-x）），若f（x）= a • b +1． （I）求函数f（x）的解析式和最小正周期； （II）若 x∈[0， π 2 ]，求f（x）的最大值和最小值．

可能感兴趣的题目：

已知向量

a

=（cosx，2cosx），向量

b

=（2cosx，sin（π-x）），若f（x）=

a

•

b

+1．
（I）求函数f（x）的解析式和最小正周期；
（II）若 x∈[0，

π

2

]，求f（x）的最大值和最小值．