cos24°cos54°－sin24°cos144°=?
来源：学生作业帮助网 编辑：六六作业网 时间：2024/11/23 06:11:30
cos24°cos54°－sin24°cos144°=?cos24°cos54°－sin24°cos144°=?cos24°cos54°－sin24°cos144°=?cos144°=cos(90°+
cos24°cos54°－sin24°cos144°=?
cos24°cos54°－sin24°cos144°=?
cos24°cos54°－sin24°cos144°=?
cos144°=cos(90°+54°）=-sin54°
则
cos24°cos54°－sin24°cos144°=cos24°cos54°+sin24°sin54°
由cosacosb+sinasinb=cos(a-b)得
原式=cos(54°-24°)
=cos30°
=√3/2
cos24°cos54°－sin24°cos144°=?
cos24°cos54°－sin24°cos144°急!
cos24°*cos36°-sin24°*cos54°等于多少,
化简√(1-2sin24°cos24°)+sin24°
cos24°cos36°- cos66°cos54°的值.
sin21°cos24°+cos21°sin24°
cos24°cos36°-sin24°sin36°=
cos24°cos69°-sin24°sin69°等于多少
求值sin21°cos24°+cos21°sin24°过程
cos24°cos69°+sin24°sin111°
求值sin21°cos24°+cos21°sin24°过程
cos24°cos36°-cos66°cos54°=?有会做的么?
cos24°cos36°-cos66°cos54°＝?求详解
求值(sin9°cos15°-sin24°)/(sin9°sin15°+cos24°)
sin9°cos15°-sin24°/sin9°sin15°+cos24°的值为___
化简：（1）cos24°cos69°-sin24°sin111°
sin24°/cos24°x（1/tan24°）—1＝?
(sina-cosa)(cos24°-sin24°)=0 怎样求出tana=1