Re: [中學] 三角函數～

[Honor1984 (奈何上天造化弄人？)]

※ 引述《gintgonhz (Determination)》之銘言：
: 上來請教各位，請幫忙解這兩題，三角函數想融會貫通不知道有什麼祕方？XD
: https://i.imgur.com/4LYwhve.jpg
(1)

k/3 = cotθtanθ = 1

=> k = 3

(2)

11/3 = cotθ + tanθ = (secθ)^2 / tanθ

     = 1 / (sinθcosθ)

=> sinθcosθ = 3/11

: https://i.imgur.com/ihDePot.jpg

(1/2) 30 π/180 - [π/4 - (1/2) 30 π/180 - (1/4)√3]

= π/6 - π/4 + (1/4)√3

= (1/4)√3 - π/12

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推 alan23273850: 符號好美～ 另外第二題我會先讓 cot=cos/sin、tan=
→ alan23273850: sin/cos，兩個分數再相加，通分會得到很好結果
→ Honor1984   : 對