> 数学 >
sin100°cos 110° +cos100°sin110°
人气:181 ℃ 时间:2020-10-01 16:37:04
解答
sin100°cos 110° +cos100°sin110°
=sin(100°+110°)
=sin210°
=sin(180°+30°)
=-sin30°
= - 1/2
推荐
猜你喜欢
© 2025 79432.Com All Rights Reserved.
电脑版|手机版