cos5°/(sin50°+cos50°)=?

分类: 作业答案 • 2022-05-09 17:32:41

问题描述：

cos5°/(sin50°+cos50°)=?
不好意思，打错了，是根号2cos5°/(sin50°+cos50°)=?

答

cos5°/(sin50°+cos50°)
=cos5°/√2(√2/2sin50°+√2/2cos50°)
=1/√2*[cos5°/(sin50°cos45°+cos50°sin45°)]
=1/√2*cos5°/sin95°
=1/√2*1
=1/√2.
=√2/2