(x+2y) (x-2y) (x2+4y2）其中x=2 y=-1

2x(x-y)4-x2(x-y)2+xy(y-x)2 如何因式分解 2x-y=2,求[（x2+y2)-(x-y)2-2y(x-y)]/4y的值 (x2-4y2)-(x+2y)因式分解 已知M=(x,y)|y>=x2 N=(x,y)|x2+(y-a)2 y=x2+2x-4的反函数y=x2+2x-4 (x y=x2-2x+2(x 1.x2+(1+x)2+(x+x2)22.(x+y)4+(x2-y2)2+(x-y)4 已知[(x2+y2)-(x-y)2+2y(x-y)]÷4y=1,求4x/4x2-y2-1/2x+y的值如图 化简(x2+3y)(x-2y)-(y+2x)(2x-y) x2+2y^2-2x+4y^2=-3 求(x+y)^2005 因式分解；x2[x-y]+y2[x-y]2是平方 A={y|y=x2-4x+6,y属于N},B={y|y=-x2-2x+18,y属于N},求A交B. x2+4/y(x-y)的最小值 ,x>y>0 [(x+y)(x-y)-(x-y)²+2y(x-y)]÷4y 已知x.y满足X2-y2=2xy.则x-y/x+y=?x. 已知4x2+9y-4x-6y+2=0 求根号y/根号x+根号y - 根号y/根号x-根号y快. 已知4x2+9y-4x-6y+2=0 求根号y/根号x+根号y - 根号y/根号x-根号y急用. x-2y分之x-y+x2-4xy+4y的2次方分之x2-y2等于多少