已知向量
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124235343230013/SYS201310251242353432300012_ST/0.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124235343230013/SYS201310251242353432300012_ST/1.png)
,且
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124235343230013/SYS201310251242353432300012_ST/2.png)
(1)求
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124235343230013/SYS201310251242353432300012_ST/3.png)
的取值范围;
(2)求函数
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124235343230013/SYS201310251242353432300012_ST/4.png)
的最小值,并求此时x的值.
考点分析:
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设向量
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∥
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124235343230013/SYS201310251242353432300009_ST/0.png)
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