sin10°sin50°-sin50°sin70°-sin70°sin10°=?

来源：学生作业帮编辑：搜搜做题作业网作业帮分类：数学作业时间：2024/04/29 09:02:12

sin10°sin50°-sin50°sin70°-sin70°sin10°=?
请给出过程,谢谢了谢谢!

=sin10sin50-sin70sin10-sin50sin70
=sin10{sin(60-10)-sin(60+10)}-sin(60-10)sin(60+10)
=sin10(-2sin10*cos60)-sin60*sin60cos10*cos10+sin10*sin10cos60*cos60
=-sin10*sin10-3/4+sin10*sin10
=-3/4

sin10°sin50°-sin50°sin70°-sin70°sin10°=? sin10°sin30°sin50°sin70°=? 求值：sin10°sin50°sin70°sin80° sin10°×sin50°×sin70°等于多少求值：sin10°sin50°·sin70° sin10°sin50°sin70° 怎样化简求值? 正弦函数求值sin10°*sin50°*sin70° sin10°*sin50°*sin70°等于好多 sin10°×sin30°×sin50°×sin70°=（）.求详解, 求证Sin10° *Sin30° *Sin50° *Sin70° =1/16 sin10°sin30°sin50°sin70°的值为（　　） sin70°cos20°-sin10°sin50°的值是多少?,麻烦给出过程