express the following in terms of sin θ , cos θ or tan θ.
1. cos(θ - 180°)
2. tan(θ - 270°)
Trigonometry問題
2007-03-08 2:14 am
回答 (2)
2007-03-08 2:59 am
✔ 最佳答案
cos(θ - 180°)=cos(θ-180°+360°)
=cos(θ+180°)
= -cosθ
tan(θ - 270°)
=tan(θ - 270°+360°)
=tan(θ + 90°)
=tan(180°-θ)
=-tan θ
2007-03-08 2:44 am
cos(θ - 180°)= cos (180°+θ) = -cos θ (third quadrant)
tan(θ - 270°) = tan(90°+θ) = -cotθ (second quadrant)
2007-03-10 00:08:32 補充：
cotθ = 1/tanθtaushing ge answer 係錯ga~~~
tan(θ - 270°) = tan(90°+θ) = -cotθ (second quadrant)
2007-03-10 00:08:32 補充：
cotθ = 1/tanθtaushing ge answer 係錯ga~~~
參考: 自己
收錄日期: 2021-04-12 23:25:28
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