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已知点(x,y)在给出的平面区域内(如图阴影部分所示),其中A(1,1),B(2...
已知点(x,y)在给出的平面区域内(如图阴影部分所示),其中A(1,1),B(2,5),C(4,3),若使目标函数Z=ax-y(a>0)取得最大值的最优解有无穷多个,则a的值是( )
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A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102729743626075/SYS201311031027297436260007_ST/0.png)
B.1
C.4
D.
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考点分析:
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