若x2+y2=6xy则(x+y)/(x-y)= 关于x的不等式2a-x≥1有三个正整数解则a的范围是

已知x2+4y2+x2y2+1=6xy,则(x4-y4)/(2x2+xy-y2)*(2x-y)/(xy-y2)/(x2+y2/y)2= 若X2+Y2-2X-6Y+10=0 ,求（x2-y2)/xy的值 若x-y/x+y=2,则x2+2xy+y2/4xy=多少 若2x+y=0则(x2+xy+y2)/(2xy-x2)的值 已知实数x,y满足x2+xy+y2=3,则x2-xy+y2的最小值 (x-y)(x2+xy+y2) (x+y)(x2-xy+y2) x2-2xy+y2=4 x2+y2-x-y=6 解不等式x2-2xy+y2=4 x2+y2-x-y=6 解不等式 若x/y=2,求x2-2xy-3y2/x2-6xy-7y2的值 若2分之x=3分之y,求x2-6xy-7y2分之x2-2xy-3y2 x2+y2+xy=1则x+y最大值 若实数x,y满足x2+y2+xy=1,则x+y的最大值是 若实数x,y满足x2+y2+xy=1,则x+y的最大值是 若x2-xy-2y2=0,Xy不等于0,则X/Y=? 已知x.y满足X2-y2=2xy.则x-y/x+y=?x. 若X2 +y2 -4x-6y= -13 求分式x2-2y2/2xy的值 已知x2-y2=xy（xy不等于0）则x/y-y/x=____ 若xy+yz+zx=0,则3xy+x2(y+z)+y2(z+x)+z2(x+y)等于多少