题目
题型:不详难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120830-78476.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-95972.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-53216.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-95972.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-86697.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-56900.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-85955.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-93003.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-98254.png)
(1)作出这个几何体的三视图(不要求写作法).
(2)设
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-87272.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-37396.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-67881.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-93408.png)
(3) 求三棱锥
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120832-57216.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120832-50380.png)
答案
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120832-59026.png)
解析
试题分析:(1)根据几何体在三个方向的投影即可得其三视图;(2)一般地判断两直线的位置关系,都应该从平行与垂直两个方向去考虑.在本题中,直线
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-67881.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-93408.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120832-63493.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120833-54186.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120833-83078.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120833-45059.png)
(1)该几何体的三视图如下图所示:
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120833-53445.png)
(2)连接
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120832-63493.png)
因为
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120834-24701.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120833-54186.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120833-83078.png)
所以
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120833-45059.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120834-61900.png)
(3)因为
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120834-27246.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120834-12462.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120831-95972.png)
又平面
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120834-33285.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120835-98170.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120835-29526.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120835-46693.png)
由此可得
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120835-41121.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120836-88209.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120836-64329.png)
所以过E作
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120836-19597.png)
核心考点
试题【如图,已知平面平面,且四边形为矩形,四边形为直角梯形,,,,,.(1)作出这个几何体的三视图(不要求写作法).(2)设是直线上的动点,判断并证明直线与直线的位置】;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/20191021/20191021120824-94300.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120819-26507.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120819-26507.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120819-79942.png)
A.V1比V2大约多一半 | B.V1比V2大约多两倍半 |
C.V1比V2大约多一倍 | D.V1比V2大约多一倍半 |
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120810-88334.png)
(Ⅰ)证明:平面ADB⊥平面BDC;
(Ⅱ)设BD=1,求三棱锥D﹣ABC的表面积.
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120734-47188.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120735-25253.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120735-25288.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120735-30516.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120735-25253.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120735-78723.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120735-30830.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120735-34247.png)
(1)证明:
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120741-14176.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120741-49210.png)
(2)求三棱锥
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120741-29245.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191021/20191021120742-70139.png)
最新试题
- 1农用化肥和粪便的排放,会使地下水中含氮量增高,其中对人体有害的含氮污染物的主要存在形式是( )A.B.C.D.有机
- 2世界银行的重要事项部需会员国投票决定,投票权的大小与会员国认购的股本成正比。2010年4月世行发展委员会会议通过改革方案
- 3小明为了减少蚯蚓在地面爬行的阻力,在蚯蚓体表涂上一层凡士林,你认为蚯蚓会( )A.运动加快B.运动减慢C.没有任何变化
- 4阅读文段,回答问题。黄羊泉 ①上世纪五十年代初,部队在沙井子垦荒,左排长带着几名战士去找水,他们徒步穿过一片一片戈壁
- 5如图所示,空间某平面内有一条折线是磁场的分界线,在折线的两侧分布着方向相反、与平面垂直的匀强磁场,磁感应强度大小都为B。
- 6导致改革成败的根本因素是( )A.是否顺应历史发展趋势B.是否符合经济发展速度C.是否符合统治阶级利益D.改革派的
- 7今年5月30日,资阳市“牵手文明、共建和谐”文明礼仪传递活动全面启动。学校是传播文明礼仪的重要阵地,作为一名中学生,有义
- 8“幼小的水稻苗能够长大;水稻种子播种后又能长出幼苗”,这说明生物具有特性是[ ]A.生长B.生长与繁殖C.发育D
- 9移动电话与基地台之间的信息传递是利用了[ ]A.光能够传输信号B.电流能够传输信号C.电磁波能够传输信号D.振荡
- 10小题1:The audience ___________ (评论) on the performance of the
热门考点
- 1选择题。— _____ does she go to work?— She ofen walks to work . [
- 2一般认为空气中二氧化碳约占空气总体积的上.上t%.可是地球上存在许多能引起二氧化碳含量变化的因素.比d,许多动物(包括6
- 3观察漫画《一字之差》 ,回答下面问题。(1)这幅漫画说明了什么问题?
- 4王安石变法中,引起藏匿土地、隐产逃税之人最激烈反对的措施是A.均输法B.市易法C.青苗法D.方田均税法
- 5设a,b,c为实数,f(x)=(x+a)(x2+bx+c),g(x)=(ax+1)(cx2+bx+1).记集合S={x
- 6若点M(m-3,m+1)在平面直角坐标系的x轴上,则点M的坐标为______.
- 7已知等差数列{an}的前n项和为Sn,若a4=18-a5,则S8等于[ ]A.72 B.54 C.36 D.18
- 8我们享有的权利,需要来自家庭,学校,社会等保护,其中最重要最有效的保护是[ ]A、家庭保护B、学校保护C、法律保
- 9设α,β为一对共轭复数,若|α-β|=23,且αβ2为实数,则|α|=______.
- 10经过点(1,2)且与两坐标轴截距相等的直线方程为______.