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[几何] 立方体各顶点到一平面距离分别是01234567

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isee Posted 2017-11-1 09:21 |Read mode
空间中是否存在一个立方体,使得它的各顶点到一个平面的距离分别是0,1,2,3,4,5,6,7?

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色k Posted 2017-11-1 10:19
我在《撸题集》题目6.10.76(第995~997页)已经详细写过。

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 Author| isee Posted 2017-11-1 13:13
回复 2# 色k


    老题呀。。。。。。

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 Author| isee Posted 2017-11-2 11:22
回复 2# 色k


    题目6.10.76. 比我这个难啊,求棱长是四解,存在性,我见到的,只是你的第一个结果。。。。

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色k Posted 2017-11-2 13:22
回复 4# isee

确实,第一个最容易想到了,我相信很多人想不到会有另外三种情形

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 Author| isee Posted 2017-11-3 17:17
回复 5# 色k



   我见到的是这样的
jh01.jpg

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乌贼 Posted 2017-11-4 01:25
回复 2# 色k
根据撸题集不同侧时,我怎么得出4种情况:
211.png

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乌贼 Posted 2017-11-4 02:07
回复 2# 色k
原来棱长为$\sqrt{54}$时可切两刀

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色k Posted 2017-11-4 14:38
回复 7# 乌贼

没看懂

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乌贼 Posted 2017-11-4 18:20
回复 9# 色k
过正方体一顶点作平面相割,使其余七顶点到该平面距离为${d,2d,3d,4d,5d,6d,7d(d\in R^+)}$

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