Re: [中學] 空間概念

看板Math作者Honor1984 (奈何上天造化弄人？)時間1天前 (2026/03/23 00:34)推噓1(1推 0噓 3→)

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※ 引述《ChenYM (老宅男一個)》之銘言： : https://i.mopix.cc/KgVG3t.jpg

: 一直想不到怎麼把題目給的cos值扯上關係 BP = BC = 4 B對△APC的投影點O B對AC的垂足H => BH = 12/5 => OH = 6 * (1/14)√21 * 2/5 = (6/35)√21 => AO = √(27/7) => CP = [4/√(27/7)] * 6 * (1/14)√21 = 4 => △PBC = (1/4)(16)√3 = 4√3 -- ※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 117.56.175.175 (臺灣) ※ 文章網址: https://www.ptt.cc/bbs/Math/M.1774197244.A.064.html

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achibluu

03/23 00:52, 1天前 , 1^F

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achibluu

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achibluu

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