更新1:
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更新2:
已附圖
求解y=2.41是怎麼算出來的?
回答 (2)
2015-09-08 8:06 am
✔ 最佳答案
√ [ (3.2y)^2 + y^2 + (-12)^2 ] = 3.2y*3000/1600 = 9600y/1600 = 6y(3.2y)^2 + y^2 + 144 = 36y^2
( 36 - 3.2^2 - 1 ) y^2 = 144
24.76 y^2 = 144
y^2 = 14400 / 2476 = 120^2 / ( 2^2 * 619 ) = 60^2 / 619
y = 60 / √ 619 ≒ 2.4116 ... Ans
2015-11-22 1:16 am
1600=3.2y*3000/[(3.2y)^2+y^2+(-12)^2]^0.5
6y=(11.24y^2+144)^0.5
36y^2=11.24y^2+144
24.76y^2=144
y=2.41
6y=(11.24y^2+144)^0.5
36y^2=11.24y^2+144
24.76y^2=144
y=2.41
收錄日期: 2021-04-18 00:11:47
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20150907223855AAumO5N