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Form Two Mathematics Trigonometric Ratio

Form Two Mathematics Trigonometric Ratio. Presented By Simon Chan. 中二級數學. 三角比關係. 數學就是這樣簡單. 學習重點 : 餘弦 (cosine)= 鄰邊 / 斜邊. A. B. C. 認識直角三角形. 在直角三角形 ABC 中，. AB 稱為 斜邊，. AC 稱為 對邊，. 鄰近的邊 BC 則稱為 Θ 角的 鄰邊 。. 在 Θ 角 ( 即∠ BAC). 學習重點 : 餘弦 (cosine)= 鄰邊 / 斜邊.

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Form Two Mathematics Trigonometric Ratio

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  1. Form Two MathematicsTrigonometric Ratio Presented By Simon Chan

  2. 中二級數學 三角比關係 數學就是這樣簡單 學習重點: 餘弦(cosine)=鄰邊/斜邊

  3. A B C 認識直角三角形 在直角三角形ABC中， AB稱為斜邊， AC稱為對邊， 鄰近的邊BC則稱為Θ角的鄰邊。 在Θ角(即∠BAC) 學習重點: 餘弦(cosine)=鄰邊/斜邊 斜邊 對邊 Θ 鄰邊

  4. 餘弦三角比 • 適合用於任何直角三角形 2. 當Θ(0度至90度)增加時，CosΘ減少

  5. A 13 Θ B C 5 餘弦比的例子 例(1):在圖中，已知AB=13和BC=5，試求Θ的值。 解: 利用餘弦公式=鄰邊/斜邊 CosΘ=BC/AB CosΘ =5/13 Θ=67.38º (準確至四位敦有效數字) 大家快來動腦筋！ 好難呀！ 唔緊要， 再接再厲！

  6. W 60° X Y 1 餘弦比的例子 例(2):在圖中，已知XY=1和∠WYX= 60°，試 求WY的值。 哈哈,我成功啦 解: 利用餘弦公式=鄰邊/斜邊 CosΘ=XY/WY WY=1 / Cos 60° =2

  7. 多謝各位！

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