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任意角三角函数的概念

> 已知向量 p =（sinx， 3 cosx）， q =（cosx，cosx），定义函数f（x）= p • q （1）求f（x）的最小正周期T；（2）若△ABC的三边长a，b，c成等比数列，且c 2+ac-a 2=bc，求边a所对角A以及f（A）的大小．

问题：

发布时间：2024-09-07

已知向量

p

=（sinx，

3

cosx），

q

=（cosx，cosx），定义函数f（x）=

p

•

q

（1）求f（x）的最小正周期T；
（2）若△ABC的三边长a，b，c成等比数列，且c ²+ac-a ²=bc，求边a所对角A以及f（A）
的大小．

参考答案：

提问用户：zu***f9s

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已知向量 p =（sinx， 3 cosx）， q =（cosx，cosx），定义函数f（x）= p • q （1）求f（x）的最小正周期T； （2）若△ABC的三边长a，b，c成等比数列，且c 2+ac-a 2=bc，求边a所对角A以及f（A） 的大小．

可能感兴趣的题目：

已知向量

p

=（sinx，

3

cosx），

q

=（cosx，cosx），定义函数f（x）=

p

•

q

（1）求f（x）的最小正周期T；
（2）若△ABC的三边长a，b，c成等比数列，且c ²+ac-a ²=bc，求边a所对角A以及f（A）
的大小．