1 . 在平面几何里,有勾股定理:“设
的两边
,
互相垂直,则
”,拓展到空间,类比平面几何的勾股定理,“设三棱锥
的三个侧面
、
、
两两相互垂直,则可得( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0faed94a64b2dcfc6801b4fca0f16675.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/372fda494413e58995e4d827a86c9641.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1776d156423ea523de87fbca6c0b6019.png)
A.![]() |
B.![]() |
C.![]() |
D.![]() |
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2019-04-26更新
|
427次组卷
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2卷引用:河南省沁阳市第一中学2020-2021学年高二下学期密集训练(三)数学(文)试题
2 . 平面几何中有如下结论:正方形的内切圆面积为
,外接圆面积为
,则
.推广到空间可以得到类似结论:已知正方体的内切球体积为
,外接球的体积为
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/625dbbd5d5f2617b7c53acdb936b1d07.png)
__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e097c8d4c948de063796bd19f85b3a9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e0bd63f55069a3bc870915010b39225.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcbe4216740c00fd9e251fc1129aedf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4764374bd2fb78e59cd0b283637baeb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63055a5d6916f99d07fede49120753f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/625dbbd5d5f2617b7c53acdb936b1d07.png)
您最近一年使用:0次
2014高三·全国·专题练习
名校
3 . 下列推理是类比推理的是
A.![]() ![]() ![]() ![]() ![]() |
B.由![]() ![]() ![]() ![]() ![]() ![]() ![]() |
C.由圆![]() ![]() ![]() ![]() |
D.以上均不正确 |
您最近一年使用:0次
2016-12-03更新
|
1835次组卷
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8卷引用:河南省沁阳市第一中学2020-2021学年高二下学期密集训练(三)数学(文)试题
9-10高二下·江苏南通·期末
名校
4 . 请阅读下列材料:若两个正实数
满足
,那么
.证明:构造函数
,因为对一切实数
,恒有
,所以
,从而得
,所以
.根据上述证明方法,若
个正实数满足
时,你能得到的结论为_______ .(不必证明)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0158862238e250d2a2598b7d4ecd148.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/469cd7bde8b86abc995debc8f43d504f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee0e066a31a9c9c18b8c7e0592eee0fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45913ffe796167ee33fe1b19a9228b6f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22e38c541dec8fce1d26886e5ef7d21f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc2e65b8353bf846fafb6baba9a9fa21.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d53b761aa4be0bb01c5db6552f3a9dcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee0e066a31a9c9c18b8c7e0592eee0fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2e29ce68d400ad5228a1c36a4926620.png)
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5卷引用:2012届河南省焦作市高三第一次质量检测文科数学试卷
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