Re: [幾何] 高中向量

[Honor1984 (奈何上天造化弄人？)]

※ 引述《QQLeopard (QQ)》之銘言：
: https://i.imgur.com/FuRPLpS.jpg


EX : FX = 3/5 : 3/4 = 4 : 5

=> AX = (5/9)AE + (4/9)AF

      = (1/3)AB + (1/3)AC

=> OX = (1/3)OA + (1/3)OB + (1/3)OC

=> a = b = r = 1/3


: https://i.imgur.com/n87qClJ.jpg
: 兩題向量題求大神們解答感謝：）

2/3 * (BD + DC)/CD * 1/2 = 1

=> BD = 2CD

=> AD = (1/3)AB + (2/3)AC

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