F.2 to F.3數學

圖片參考：https://s.yimg.com/lo/api/res/1.2/ZQit8r6YM3UMER1bF6V.OQ--/YXBwaWQ9dHdhbnN3ZXJzO3E9ODU-/http://i.imgur.com/ZH9B85L.gif

22.
(a)
tan θ = 1/5
θ = 11.30993247° ≈ 11°
(b)
由 A 測得 C 的真方位角 = 100° + 11° = 111°

23.
考慮三角形ABC
100° + (x + 20°) + x = 180° [三角形內角和]
120° + 2x = 180°
2x = 60°
x = 30°
考慮三角形ABD
100° + x + y = 180° [三角形內角和]
100° + 30° + y = 180°
y = 50°

26.
設所求的高度為 h m
tan 16° = h/570
h = 570 tan 16° = 163.4448699
所求的高度約為 163 m。

28.
∠ADC = ∠DAB = 40° [交錯角, AB // CE]
∠ADG = 90° [已知]
∠CDG = 90° - ∠ADC = 90° - 40° = 50°
∠DGH = 50° [已知]
因此, ∠CDG = ∠DGH
所以, CE // FH [交錯角相等]


圖片參考：https://s.yimg.com/lo/api/res/1.2/.j9m2lKXgvCkX788BBlbIQ--/YXBwaWQ9dHdhbnN3ZXJzO3E9ODU-/http://www.stormmediagroup.com/upload/frontend/de64aa90-6c17-431f-bf5d-97c0a71ad961/2dc24da2-a849-4ec6-9b91-ea74994fc0aa.gif