[中學] 距離平方和最小的問題
範圍:高二數學
題目:大概是說 xy平面上有一直線且其兩側有A、B兩點
╴2 ╴2
今欲在線上求一點P,使得PA + PB最小?
求法大概都會先假設線上的動點(參數式)
然後依題意代入,列出二次式,再配方求值即可!!
╴ ╴
但今年遇到一位學生使用PA + PB最小的方法(連起AB即找到P點)
我只能跟他說平方和的P點與距離和最小的P點不同
但總感覺應該有更直觀的例子或說明(我有提到△的重心與費瑪點不同)
但想請教各位板上神人 不知有代數或其他更容易懂的說法? 謝謝各位...
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04/10 21:18, , 1F
04/10 21:18, 1F
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04/10 21:21, , 2F
04/10 21:21, 2F
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04/10 21:22, , 3F
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04/10 21:28, , 7F
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04/10 21:28, , 8F
04/10 21:28, 8F
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04/10 22:42, , 9F
04/10 22:42, 9F
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04/10 23:43, , 10F
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04/11 00:22, , 11F
04/11 00:22, 11F
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04/11 00:24, , 12F
04/11 00:24, 12F
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04/11 00:27, , 13F
04/11 00:27, 13F
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04/11 00:27, , 14F
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04/11 00:28, , 15F
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04/11 00:35, , 27F
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04/11 00:36, , 28F
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04/11 00:36, , 29F
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04/11 00:38, , 32F
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01/02 15:43,
5年前
, 34F
01/02 15:43, 34F
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07/07 12:01,
4年前
, 35F
07/07 12:01, 35F
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