x2-2xy+y2/x2-y2其中x=√3+1,y=√3-1

x2-2xy+y2/x2-y2其中x=√3+1,y=√3-1 思考题：先化简,再求值：(xy-y2)÷x2-2xy+y2/y×x2-y2/y2,其中x=1/2,y=-1 (x2-2xy+y2)-(x2+2xy+y2)=什么 化简求值x2+3xy2y2分之-2x2-xy+y2,其中x=2y 1.(x-y)(x2+xy+y2) 2.求值x2(x-1)-x(x2+x-1),其中x=2分之一 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X2+xy-2y2=0,则（x2+3xy+y2)/x2+y2=? x的平方+ xy-2y的平方=0,则(X2+3Xy+Y2)/(X2+Y2)=__x的平方+ xy-2y的平方=0,则(X2+3Xy+Y2)/(X2+Y2)=__其中(X2+3Xy+Y2)/(X2+Y2)=__的2为平方 x2-2xy-3y2=0,其中x,y均不为零,求（y-x）/x2-xy/2x-y-y2/xy-x 已知x2+4y2+x2y2+1=6xy,则(x4-y4)/(2x2+xy-y2)*(2x-y)/(xy-y2)/(x2+y2/y)2= 1.已知正数x,y满足x2-y2=2xy,求(x-y)/(x+y)的值2.若x2+xy-2y2=0则(x2+3xy-2y2)/x2-2y2)=_________3.先化简,后求值：(3-x)/(x-2)除以（x+2-2/(x-2)）,其中x=2√2  已知x2+y2+4x-2y+5=0,求x2+2xy+y2值 如果2/x=3/y,那么x2-2xy+3y2/7x2-y2? 若X2+Y2-2X-6Y+10=0 ,求（x2-y2)/xy的值 5x2-3xy-4y2-11xy+(-7x2)-(-2y2),其中x2+y2=7,xy=-2,求值 (x-y)(x2+xy+y2) (x+y)(x2-xy+y2) 4x2-y2/x2-2xy+y2 +(2x-y)/2x2-2xy