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设x,y满足约束条件,若目标函数z=ax+by(a>0,b>0)的值是最大值为1...
设x,y满足约束条件
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024183424673825949/SYS201310241834246738259007_ST/0.png)
,若目标函数z=ax+by(a>0,b>0)的值是最大值为12,则
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024183424673825949/SYS201310241834246738259007_ST/1.png)
的最小值为( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024183424673825949/SYS201310241834246738259007_ST/2.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024183424673825949/SYS201310241834246738259007_ST/3.png)
C.
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D.4
考点分析:
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024183424673825949/SYS201310241834246738259004_ST/0.png)
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024183424673825949/SYS201310241834246738259004_ST/1.png)
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