设
为多面体
的一个顶点,定义多面体
在点
处的离散曲率为
,其中
(
,
)为多面体
的所有与点
相邻的顶点,且平面
,平面
,
,平面
和平面
遍历多面体
的所有以
为公共点的面.
(Ⅰ)任取正四面体的一个顶点,该点处的离散曲率为______ ;
(Ⅱ)如图所示,已知长方体
,
,
,点
为底面
内的一个动点,则四棱锥
在点
处的离散曲率的最小值为______ ;
![](https://img.xkw.com/dksih/QBM/2019/4/24/2189553408671744/2190033901625344/STEM/d702c3f66ea94eca9f04400c83427802.png?resizew=265)
(Ⅲ)图中为对某个女孩面部识别过程中的三角剖分结果,所谓三角剖分,就是先在面部取若干采样点,后用短小的直线段连接相邻三个采样点形成三角形网格.区域
和区域
中点的离散曲率的平均值更大的_______ .(填写“区域
”或“区域
”)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2fe17927b79a9ab83ed1a35b904bd47.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1fc903da7487dcd2f069b50a5cf2bd5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/940cd957b9db25326a0c7a413df7f1d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/835c74bbb8c61dd2d2f008664a8c8810.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/183f3fdb3204864ff2f60c8c1dac2f2a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db59863ffec5fa450ab8342fd8675c2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa5e9bd516f6282483b92cfe6074623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9d7f18c3c9dae7e6d4f2e96281289f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f733e19f18ab01a3c022331805ed58a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
(Ⅰ)任取正四面体的一个顶点,该点处的离散曲率为
(Ⅱ)如图所示,已知长方体
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0424446817f60c18f8e4e3cc202ad99.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/829018a6ca0aff95d89e3f7cd943274e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c3a9df7d8e2ad07128d69fb50962a4b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632f2bf1cd0435041fa04b01901d1c8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://img.xkw.com/dksih/QBM/2019/4/24/2189553408671744/2190033901625344/STEM/d702c3f66ea94eca9f04400c83427802.png?resizew=265)
(Ⅲ)图中为对某个女孩面部识别过程中的三角剖分结果,所谓三角剖分,就是先在面部取若干采样点,后用短小的直线段连接相邻三个采样点形成三角形网格.区域
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://img.xkw.com/dksih/QBM/2019/4/24/2189553408671744/2190033901625344/STEM/5e7f249d436a4d5eb004497f932097c3.png?resizew=153)
18-19高一下·北京海淀·期中 查看更多[2]
更新时间:2019-04-25 14:18:17
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