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任意角三角函数的概念

> 已知f （x）= 3 2 sin2x-cos 2- 1 2 ，（x∈R）．（Ⅰ）求函数f（x）的最小值和最小正周期；（Ⅱ）设△ABC的内角A、B、C的对边分别为a、b、c，且c= 3 ，f （C）=0，若 m =（1，sinA）与 n =（2，sinB）共线，求a，b的值．

问题：

发布时间：2024-09-09

已知f （x）=

3

2

sin2x-cos ²-

1

2

，（x∈R）．
（Ⅰ）求函数f（x）的最小值和最小正周期；
（Ⅱ）设△ABC的内角A、B、C的对边分别为a、b、c，且c=

3

，f （C）=0，若

m

=（1，sinA）与

n

=（2，sinB）共线，求a，b的值．

参考答案：

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已知f （x）= 3 2 sin2x-cos 2- 1 2 ，（x∈R）． （Ⅰ）求函数f（x）的最小值和最小正周期； （Ⅱ）设△ABC的内角A、B、C的对边分别为a、b、c，且c= 3 ，f （C）=0，若 m =（1，sinA）与 n =（2，sinB）共线，求a，b的值．

可能感兴趣的题目：

已知f （x）=

3

2

sin2x-cos ²-

1

2

，（x∈R）．
（Ⅰ）求函数f（x）的最小值和最小正周期；
（Ⅱ）设△ABC的内角A、B、C的对边分别为a、b、c，且c=

3

，f （C）=0，若

m

=（1，sinA）与

n

=（2，sinB）共线，求a，b的值．