I thought it would be like this:
|sinx|=|cosx|
|sinx|-|cosx|=0 and then divided everything by either sinx or cosx so I got
Tgx-1=0 (or 1-ctgx=0) x=pi/4 + pin.. but the answer is different..
收錄日期: 2021-04-18 14:40:21
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20160317081357AA3wSe2