在Rt△ABC中,∠C=90°,若sin A= 12 ,则∠B的度数是( )_刷题宝

题干

在Rt△ABC中,∠C=90°,若sin A=

1

2

,则∠B的度数是( )

A：30°

B：45°

C：60°

D：90°

上一题下一题 0.0难度选择题更新时间:2018-05-31 08:39:17

答案(点此获取答案解析）

C

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