X*2+X(Y-1)-（2Y*2-7Y+6）怎么变形等于（X+Y+2)(X+2Y-3X*2+X(Y-1)-（2Y*2-7Y+6）怎么变形等于（X+Y+2)(X+2Y-3)

[(-x-y)(-x+y)-(x+y)^2-x(y-y^2)}÷1/2y x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 x+2y=2x+y+1=7x-y 求：2x-y? {6(x-y)-7(x+y)=21 {2(x-y)-5(x+y)=-1 化简y(x+y)+(x+y)(x-y)-x^2 把(x+y),(x-y)个作为一个整体合并同类项1,7(x+y)-2(x+y)-4(x+y)+2(x+y)2,(x-y)²＋2(x-y)－(x-y)－2(x-y)² 1、(-7x^y)(2x^y-3xy^3+xy) 2、((x-y)^6)/((y-x)^3)/(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) 化简3(x-y)-7(x--y)+2(y-x) 计算:1/(x-y)-1/(x+y)-2y/(x^2+y^2)-4y^3/(x^4+y^4)-8x^7/(x^8+y^8) 已知：2x+y=6,x-3y=1 求7y(x-3y)(x-3y)-2(3y-x)(3y-x) 1、y-x/x²-y²2、(x-y)(y-z)(z-x)/(z-y)(y-x)(x-z) [(x-y)^2-(x+2y)(x-2y)]/y (x-y)(2x-y-1) 计算:y-x分之x+y+x-y分之y-y-x分之2x-y 因式分解x(x+y)(x-y)-x(x+y)^2 2y(x+二分之一y)-[(x+y)(x-y)+2y(y+x)],其中|x-1|=2