题目内容
(本小题满分12分)
如图,已知圆锥的轴截面ABC是边长为
的正三角形,O是底面圆心.
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/201408240049209893195.png)
(1)求圆锥的表面积;
(2)经过圆锥的高
的中点
作平行于圆锥底面的截面,求截得的圆台的体积.
如图,已知圆锥的轴截面ABC是边长为
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004920973455.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/201408240049209893195.png)
(1)求圆锥的表面积;
(2)经过圆锥的高
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921005387.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921020321.png)
(1)
(2)![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/201408240049210672348.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/201408240049210361302.png)
(2)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/201408240049210672348.png)
试题分析:解:(1)由题意可知
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921083587.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921098376.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921129426.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921098376.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921176323.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921098376.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921207399.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921098376.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/201408240049212541332.png)
(2)在
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921270617.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921285641.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/201408240049213011199.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921317354.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921005387.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921363708.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921098376.png)
∴小圆锥的高h¢=
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921395420.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921098376.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921504321.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824004921098376.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140824/201408240049215352351.png)
点评:解决的关键是能得到圆锥的底面半径和高度,以及台体的底面的半径以及高度,属于基础题。
![](http://thumb.zyjl.cn/images/loading.gif)
练习册系列答案
相关题目