题目内容

已知曲面z=x2+y2上点P处的切平面平行于平面2x+2y+z一1=0，则点P的坐标是 ( )

A. (1，一1，2)
B. (一1，1，2)
C. (1，1，2)
D. (一1，一1，2)

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