Yahoo 知識+ 將於 2021 年 5 月 4 日 (美國東岸時間) 停止服務，而 Yahoo 知識+ 網站現已轉為僅限瀏覽模式。其他 Yahoo 資產或服務，或你的 Yahoo 帳戶將不會有任何變更。你可以在此服務中心網頁進一步了解 Yahoo 知識+ 停止服務的事宜，以及了解如何下載你的資料。
Trigonometry
15. Without using a calculator, solve 2tanθ = 1/cos30° for θ, where 0°<θ<90°.
16. Without using a calculator, solve √3-2tan60°sinθ = 0 for θ, where 0°<θ<90°.
17. Without using a calculator, solve (1/2)tanθ = 2(1-sin30°)sin30° for θ, where 0°<θ<90°.
please help me to solve,thanks.
1 個解答
- 知足常樂Lv 78 年前最愛解答
15. Without using a calculator, solve 2tanθ = 1/cos30° for θ, where 0°<θ<90°.
2tanθ = 1/[√(3)/2] = 2/√3
tanθ = 1/√3
θ = 30°
16. Without using a calculator, solve √3-2tan60°sinθ = 0 for θ, where 0°<θ<90°.
√3 - 2tan60°sinθ = 0
√3 - 2√3sinθ = 0
1 - 2sinθ = 0
sinθ = 1/2
θ = 30°
17. Without using a calculator, solve (1/2)tanθ = 2(1-sin30°)sin30° for θ, where 0°<θ<90°.
(1/2)tanθ = 2(1-sin30°)sin30°
tanθ = 4(1-1/2)(1/2)
tanθ = 4(1/2)(1/2)
tanθ = 1
θ = 45°
