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> 若sinαtanα≥0，k∈Z，则角α的集合为（　　） A．[2kπ- π 2 ，2kπ+ π 2 ] B．（2kπ- π 2 ，2kπ+ π 2 ） C．（2kπ- π 2 ，2kπ+ π 2 ）∪{2kπ-π} D．以上都不对

问题：

发布时间：2024-09-07

若sinαtanα≥0，k∈Z，则角α的集合为（　　）

A．[2kπ-

π

2

，2kπ+

π

2

] B．（2kπ-

π

2

，2kπ+

π

2

）

C．（2kπ-

π

2

，2kπ+

π

2

）∪{2kπ-π} D．以上都不对

参考答案：

提问用户：nF***e3N

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若sinαtanα≥0，k∈Z，则角α的集合为（ ） A．[2kπ- π 2 ，2kπ+ π 2 ] B．（2kπ- π 2 ，2kπ+ π 2 ） C．（2kπ- π 2 ，2kπ+ π 2 ）∪{2kπ-π} D．以上都不对

可能感兴趣的题目：

若sinαtanα≥0，k∈Z，则角α的集合为（　　）

A．[2kπ-

π

2

，2kπ+

π

2

] B．（2kπ-

π

2

，2kπ+

π

2

）

C．（2kπ-

π

2

，2kπ+

π

2

）∪{2kπ-π} D．以上都不对