题目内容
(本题满分12分)
已知函数
,(1)求函数
极值.(2)求函数
在
上的最大值和最小值.
已知函数
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419363641.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419394447.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419394447.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419425510.png)
(1)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154196283554.png)
(2)由(1)可知,
的极大值为2,极小值为-2
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419940235.png)
…………………………………………………………10分
∴当
时,
当
时, ![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154201581761.png)
![]() | ![]() | -1 | ![]() | 1 | ![]() |
![]() | + | 0 | - | 0 | + |
![]() | ![]() | 极大值 | ![]() | 极小值 | ![]() |
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154196283554.png)
(2)由(1)可知,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419394447.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419940235.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154200021023.png)
∴当
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215420080391.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154201111717.png)
当
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215420127332.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154201581761.png)
(1)求函数
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419394447.png)
(2)求函数
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419394447.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419425510.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154200021023.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154202991215.png)
解:(1)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419940235.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419363641.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215420377924.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154203923243.png)
![]() | ![]() | -1 | ![]() | 1 | ![]() |
![]() | + | 0 | - | 0 | + |
![]() | ![]() | 极大值 | ![]() | 极小值 | ![]() |
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215420579168.png)
………………………………………………………………………………………………6分
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154205953522.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419394447.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215419940235.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154200021023.png)
∴当
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215420080391.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154201111717.png)
当
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823215420127332.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232154201581761.png)
![](http://thumb.zyjl.cn/images/loading.gif)
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