先化简 2X^2+Y^2（2Y^2-3X^2）-2（Y^2-2X^2）,其中X=-1,Y=22X^2+Y^2（2Y^2-3X^2）-2（Y^2-2X^2）,其中X=-1，Y=2

x(x-y)2-(y-x)3 x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 [2/3x-2/x+y(x+y/3x-x-y)]/x-y/x 化简：{2/3x-2/(x+y)[(x+y)/3x-x-y]}/(x+y)/x 计算2/3x-2/x+y(x+y/3x-x-y)/x-y/x 化简3x-2/(x+y)[(x+y)/3x-x-y]÷(x-y)/x 化简y(x+y)+(x+y)(x-y)-x^2 计算：x+2y/x-y+2x/y-x-3y/x-y 化简:(x-3y)(x+y)-(x-2y)(x+2y)-(x-y)平方 [(3x+y)(x-y)-(2x+3y)(x-y)]*(x-y) (x+y)(x-y)-(x-y)^2如题 (x+y)(x-y)-(x-y)^2 【2(x-y)(x-y)(x-y)-8(x-y)(x-y)(x+y)+6y(x-y)(x-y)]/2(x-y)(x-y) 因式分解x(x+y)(x-y)-x(x+y)^2 2X(2X-3Y)-3Y(X+Y) (-2x y)^2-(3y-x)(-x-3y) （x+2y)^2-(x+y)(3x-y) 计算(x+y)(x+y)^2(-x-y)^3 化简:5(x-y)+2(x+y)-3(x-y)