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已知x,y满足且目标函数z=2x+y的最大值为7,最小值为1,则=( ) A.2...
已知x,y满足
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024183525281076055/SYS201310241835252810760008_ST/0.png)
且目标函数z=2x+y的最大值为7,最小值为1,则
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024183525281076055/SYS201310241835252810760008_ST/1.png)
=( )
A.2
B.1
C.-1
D.-2
考点分析:
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