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[几何] 两个立体几何问题

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Shiki Posted 2019-5-20 22:45 |Read mode
Last edited by Shiki 2019-5-20 23:091.与空间四边形$ABCD$四个顶点距离相等的面共有多少个?
2.$\alpha \beta \gamma $为三个两两垂直的平面$\alpha \cap \beta =OX ,\beta \cap \gamma =OY ,\gamma \cap \beta =OZ$
空间一点$P$到面$\alpha,\beta,\gamma$的距离分别为$2,3,6$,求$OP$的长
= =

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色k Posted 2019-5-20 22:49
稍微想了下应该是7个吧

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 Author| Shiki Posted 2019-5-20 22:52
回复 2# 色k


    擦,k神一想就和参考答案一样,是面两边分别是2,2和1,3个点吗

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色k Posted 2019-5-20 22:58
回复 3# Shiki

对啊,2-2 对应三对棱,1-3 对应四顶点,所以就7个咯。

至于第二题看不懂

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 Author| Shiki Posted 2019-5-20 23:01
回复 4# 色k


    我最开始想不到1,3
第二题就是P点到O为顶点三棱锥的三个侧面距离2,3,6,求OP

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色k Posted 2019-5-20 23:04
回复 5# Shiki

那些侧面的夹角是多少你没给,咋求啊

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 Author| Shiki Posted 2019-5-20 23:08
回复 6# 色k


    百度了一下,题目有误应为三个两两垂直的平面,这样就没啥做的了

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