若|x-1/2|+(2y+1)2=0,则x2+y2的值是a.3/8 b.1/8 c.-1/8 d.-3/8

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若|x-1/2|+(2y+1)2=0,则x2+y2的值是a.3/8 b.1/8 c.-1/8 d.-3/8
若|x-1/2|+(2y+1)2=0,则x2+y2的值是
a.3/8 b.1/8 c.-1/8 d.-3/8

若|x-1/2|+(2y+1)2=0,则x2+y2的值是a.3/8 b.1/8 c.-1/8 d.-3/8
因为|x-1/2|+(2y+1)2=0,
所以x=1/2,y=-1/2
x^2+y^2=(1/2)^2+(-1/2)^2=1/4+1/4=1/2

题目对吗?

绝对值+平方=0只可能2个都为零,即X=1/2,Y=-1/2,所以x2+y2=1/2

单论选择题来做:由上面方程可以得出2y+1<=0,即y<=-1/2,y^2>=1/4。由x^2+y^2>=0,排除c,d;又x^2+y^2>=y^2>=1/4>1/8,排除b,所以选a

题不对