4cos1°sin1°cos2°csc4°是如何化簡成1的 求詳解?

2021-01-28 10:11 pm
更新1:

2cos 1sin 1是如何變成(sin 2(1))???

回答 (1)

2021-01-28 10:24 pm
✔ 最佳答案
4cos 1sin 1cos 2csc 4
=2(2cos 1sin 1)cos 2(1/sin 4)
=2(sin 2(1))cos 2 (1/sin 4)
=(2sin 2cos 2)(1/sin 4)
=(sin 2(2))(1/sin 4)
=(sin 4)(1/sin 4)
=1

三角學恒等式:
sin 2x=2sin xcos x


收錄日期: 2021-04-24 08:10:46
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20210128141122AAUhFib

檢視 Wayback Machine 備份