A.
B.
C.
D.
答案:C
用代数式表示“x与y的差的平方减去x与y的平方差”应是( )
A.(x2-y2)-(x-y)2
B.(x-y)2-(x2-y2)
C.(x-y)2-(x-y2)
D.(x-y2)-(x-y)2
ZPW-2000两相邻区段的衰耗器面板"轨道占用"指示灯亮红灯该如何查找?