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任意角三角函数的概念

> 已知θ是三角形中的一个最小内角，且 acos2 θ 2 +sin2 θ 2 -cos2 θ 2 -asin2 θ 2 =a+1，则a的取值范围是（　　） A．a＜-1 B．a＞-1 C．a≤-3 D．a≥-3

问题：

发布时间：2024-09-08

已知θ是三角形中的一个最小内角，且 acos2

θ

2

+sin2

θ

2

-cos2

θ

2

-asin2

θ

2

=a+1，则a的取值范围是（　　）

A．a＜-1 B．a＞-1 C．a≤-3 D．a≥-3

参考答案：

提问用户：cm***gPL

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已知θ是三角形中的一个最小内角，且 acos2 θ 2 +sin2 θ 2 -cos2 θ 2 -asin2 θ 2 =a+1，则a的取值范围是（ ） A．a＜-1 B．a＞-1 C．a≤-3 D．a≥-3

可能感兴趣的题目：

已知θ是三角形中的一个最小内角，且 acos2

θ

2

+sin2

θ

2

-cos2

θ

2

-asin2

θ

2

=a+1，则a的取值范围是（　　）

A．a＜-1 B．a＞-1 C．a≤-3 D．a≥-3