由X2-2XY+Y2-X+Y-1=0得到X-Y的值为.
由X2-2XY+Y2-X+Y-1=0得到X-Y的值为.
若实数xy满足x2十y2-2x+4y=0,则x-2y的最大值为多少?
已知x2+y2+2x-6y+10=0,求xy的值
设二元函数z=x2+xy+y2—x-y,x2+y2≤1,求它的最大值和最小值.
x2+y2+xy-3y+3=0 求x的y次方
已知xy为实数求x2-2xy+6y2-14x-6y+72的最小值
若x2y+xy2=30,xy=6,求下列代数式的值:(1)x2+y2;(2)x-y.
若x2-2xy-y2-x+Y-1=0 求x-y的值
(x+y)(x+y+1)=0 求x2+y2+2xy的值
x2-(a+b)xy+aby2 x2+4xy-5y2 x2-5x+3 2x2+xy-y2-4x+5y-6
已知实数x,y满足(x2)+(y2)-xy+2x-y+1=0,求x,y的值
已知实数x、y满足X2+y2-xy+2x-y+1=0,试求x、y的值