题目
题型:不详难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120626-36776.jpg)
(1)证明: BC1//平面A1CD;
(2)设AA1="AC=CB=1," AB=
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120626-58931.png)
答案
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120626-26783.png)
解析
试题分析:(1)先由三角形中位线与底边平行得到
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120627-92837.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120627-39289.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120627-59177.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120627-64431.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120628-37575.png)
解:(1)连结
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120628-65987.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120629-42864.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120629-10136.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120629-10136.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120628-65987.png)
又D是AB中点,连结DF,则
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120627-92837.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120630-54379.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120630-23858.jpg)
(2)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120630-79181.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120630-47935.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120631-43174.png)
核心考点
试题【如图,直三棱柱ABC-A1B1C1中, D、E分别是AB,BB1的中点.(1)证明: BC1//平面A1CD;(2)设AA1="AC=CB=1," AB=,求三】;主要考察你对柱锥台的表面积等知识点的理解。[详细]
举一反三
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120619-63636.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120608-10955.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120608-13135.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120608-39926.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120608-98067.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120608-13135.png)
影为
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120608-54584.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120609-44956.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120609-49496.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120610-82496.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120608-13135.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120610-26235.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120608-10955.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120553-58810.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120554-74139.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120554-60367.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120554-98834.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120554-74285.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120554-56161.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120554-14835.png)
方形沿
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120554-45589.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120554-60782.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120554-36293.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120554-53363.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120554-70643.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120555-66226.png)
A.![]() | B.![]() | C.![]() | D.![]() |
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120542-19188.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120543-61657.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120543-20717.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120543-14539.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120543-50121.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120544-60263.png)
A.![]() | B.![]() | C.![]() | D.![]() |
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120545-23884.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120536-24492.png)
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