sin47°-sin17°cos30°/sin73°化简求值

分类: 作业答案 • 2023-01-20 10:27:27

问题描述：

答

(sin47°-sin17°cos30°)/sin73°
=[sin(30°+17°)-sin17°cos30°]/cos17°
=(sin30°cos17°+sin17°cos30°-sin17°cos30°)/cos17°
=sin30°cos17°/cos17°
=sin30°
=1/2