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任意角三角函数的概念

> 设函数 f(x)=cos2(x+ π 4 )-sin2(x+ π 4 )，x∈R，则函数f（x）是（　　） A．最小正周期为π的奇函数 B．最小正周期为π的偶函数 C．最小正周期为 π 2 的奇函数 D．最小正周期为 π 2 的偶函数

问题：

发布时间：2024-09-08

设函数 f(x)=cos2(x+

π

4

)-sin2(x+

π

4

)，x∈R，则函数f（x）是（　　）

A．最小正周期为π的奇函数

B．最小正周期为π的偶函数

C．最小正周期为

π

2

的奇函数

D．最小正周期为

π

2

的偶函数

参考答案：

提问用户：2H***CKk

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设函数 f(x)=cos2(x+ π 4 )-sin2(x+ π 4 )，x∈R，则函数f（x）是（ ） A．最小正周期为π的奇函数 B．最小正周期为π的偶函数 C．最小正周期为 π 2 的奇函数 D．最小正周期为 π 2 的偶函数

可能感兴趣的题目：

设函数 f(x)=cos2(x+

π

4

)-sin2(x+

π

4

)，x∈R，则函数f（x）是（　　）

A．最小正周期为π的奇函数

B．最小正周期为π的偶函数

C．最小正周期为

π

2

的奇函数

D．最小正周期为

π

2

的偶函数