(x-1)^2+y^2+2y+1=o.求1/8xy的值
来源:百度知道 编辑:UC知道 时间:2024/05/29 03:33:25
(x-1)^2+y^2+2y+1=0
(x-1)^2+(y+1)^2=0
(x-1)^2=0,(y+1)^2=0
x-1=0,y+1=0
x=1,y=-1
1/8xy=1/8*1*(-1)=-1/8
(x-1)^2+y^2+2y+1=o
(x-1)^2+(y+1)^2=0
两个都是平方的,可以得出两个平方都是0
那么X=1 Y=-1
1/8XY= -1/8
整理后(x-1)^2+(y+1)^2=0
x=1 y=-1
故原式=-1/8
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