* [三角函數關係(IG動畫)] (https://www.instagram.com/reel/C0Eicp7O4zk/)  * [sin&cos特殊度值記憶法(IG動畫)](https://www.instagram.com/reel/CzY_yyMNa52/)  * [$sin^2+cos^2=1$ (IG動畫)](https://www.instagram.com/reel/CxfHD8Ktyhg/)  * [三角函數-強森六邊形(網頁連結)](https://sylworld.666forum.com/t310-topic) 
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