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> 设双曲线4x 2-y 2=1的两条渐近线与直线x= 围成的三角形区域（包含边界）为D，P（x，y)为D内的一个动点，则目标函数z= x-y的最小值为 [ ] A．-2 B． C．0 D．

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发布时间：2024-09-10

设双曲线4x ²-y ²=1的两条渐近线与直线x= 围成的三角形区域（包含边界）为D，P（x，y)为D内的一个动点，则目标函数z= x-y的最小值为
[ ]
A．-2
B．
C．0
D．

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