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任意角三角函数的概念

> 已知函数 f(x)=sin( π 2 +x)cosx-sinxcos(π-x)，（1）求函数f（x）的最小正周期；（2）在△ABC中，已知A为锐角，f（A）=1， BC=2，B= π 3 ，求AC边的长．

问题：

发布时间：2024-09-09

已知函数 f(x)=sin(

π

2

+x)cosx-sinxcos(π-x)，
（1）求函数f（x）的最小正周期；
（2）在△ABC中，已知A为锐角，f（A）=1， BC=2，B=

π

3

，求AC边的长．

参考答案：

提问用户：M9***gn5

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已知函数 f(x)=sin( π 2 +x)cosx-sinxcos(π-x)， （1）求函数f（x）的最小正周期； （2）在△ABC中，已知A为锐角，f（A）=1， BC=2，B= π 3 ，求AC边的长．

可能感兴趣的题目：

已知函数 f(x)=sin(

π

2

+x)cosx-sinxcos(π-x)，
（1）求函数f（x）的最小正周期；
（2）在△ABC中，已知A为锐角，f（A）=1， BC=2，B=

π

3

，求AC边的长．