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[几何] 2019文科数学三模11题 立体几何

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走走看看 posted 2019-5-14 13:27 |Read mode
2019合肥市三模文科数学题11.png

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kuing posted 2019-5-14 13:51
画个图一看就出来了,如下图,显然 `AB` 是中位线,故 `AB=4`,所以重合部分 `V=\frac13\pi\cdot2^2\cdot2=\frac83\pi`。
QQ截图20190514135128.png

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乌贼 posted 2019-5-14 14:03
211.png
$ V=\dfrac{2\times 2^2\pi}{3}=\dfrac{8\pi}{3} $

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kuing posted 2019-5-14 14:10
回复 3# 乌贼

慢了十几分钟

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original poster 走走看看 posted 2019-5-14 17:31
两位大师都挺神的。很快就能做出来。佩服!

不过,这两个圆锥也可能没有共同部分,比如一个在左边,一个在右边。一个在上面,一个在下面,因此感觉这道题出得不是很严谨。

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kuing posted 2019-5-14 17:53
回复 5# 走走看看

人家分明写着“圆锥 `SO_1`, `SO_2`”,你没认真读题,还怪人家出题不严谨?

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青青子衿 posted 2019-5-14 18:04
Last edited by 青青子衿 2019-5-14 18:36回复 6# kuing
所以就应当让他把题目码成文字,就会尽可能地避免这样的问题
题干等同于说了:两个圆锥的顶点公共,两个圆锥的顶点都为\(\,S\,\),顶点所在的球也是两个底面圆周所在的球

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isee posted 2019-5-14 20:17
回复 7# 青青子衿

别别,楼主码字是,可真是把汉字和公式全码一起,看着难受极了。

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