sin75度等于几分之几
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:2024/08/04 06:15:13
sin75度等于几分之几
![sin75度等于几分之几](/uploads/image/z/17390462-14-2.jpg?t=sin75%E5%BA%A6%E7%AD%89%E4%BA%8E%E5%87%A0%E5%88%86%E4%B9%8B%E5%87%A0)
sin75°=sin(45°+30°)
=sin45°cos30°+sin30°cos45°
=√2/2·√3/2+1/2·√2/2
=√6/4+√2/4
=(√6+√2)/4
=sin45°cos30°+sin30°cos45°
=√2/2·√3/2+1/2·√2/2
=√6/4+√2/4
=(√6+√2)/4