寫個計算步驟出來. 要準確&詳細!!
13.
sin(30-x) cos(30-x) = (root3) /2
The ans. is 120', 150', 300', 330'
6.
tan^2 x + cot^2 x = 2
ans. 180'n +- 45'
8.
sin 4x + sin x = 0
ans. 72'n or 240'n +- 60'
10.
sin x = cot 2x
ans. 120'n + 30' or 360'n - 90'
14.
cos x + cos 7x = cos 4x
ans. 90'n +- 22.5' or 120'n +- 20'
[急] F.4數學, 有20點
2008-03-01 4:44 am
回答 (1)
2008-03-01 7:03 am
✔ 最佳答案
Please refer to the following solution:圖片參考：http://hk.geocities.com/stevieg_1023/re0.gif
圖片參考：http://hk.geocities.com/stevieg_1023/re1.gif
圖片參考：http://hk.geocities.com/stevieg_1023/re2.gif
收錄日期: 2021-04-25 17:20:05
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080229000051KK03030