#2 4tanΘ/cos(90-Θ)-1/sin(90-Θ)
更新1:
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2條數,(三角比)
回答 (1)
2009-04-21 5:41 am
✔ 最佳答案
#1 1/tan Θ = (tan Θ)^4
1 = (tan Θ)^5
tan Θ = 1
Θ=(180n + 45) , (n = 0,1,2,3......)
#2
4tanΘ / cos(90-Θ) - 1/sin(90-Θ)
4(sinΘ/cosΘ) / sinΘ - 1/cosΘ
=4/cosΘ - 1/cosΘ
= 3 / cosΘ
2009-04-20 21:58:51 補充：
For #1 :
Θ=(180n + 45°) , (n = ± 0,1,2,3......)
Θ= 45° or 225° for 0° <= Θ < 360°
收錄日期: 2021-04-21 22:01:59
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20090420000051KK01619