2x+(5x-3y)-(6x+2y) ; -5+（-x的2次方+4x）-（-5+3x的2次方）；（x的3次方+3x的2次方-5x+6）-（2x的2次方-5x+1）-（x的3次方+x的2次方-2）；-（2a-b）-2[a-(2a-b)];2(a+b)-[4(a+b)-3(a+b)2次方]-[5(a+b)2次方+(a+b)];ab-2 ab-[3

[2(x-y)^5-8(x-y)^2(x+y)+6y(x-y)^2]÷2(x-y)^2[2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2]÷2(x-y)^2 2(2x+3y)(3x+2y)-(6x-y)(2x-5y) x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2 因式分解x次方-y次方+5x-y+6【x-y+2】【x+y+3】 6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5 化简:5(x-y)+2(x+y)-3(x-y) 【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3x^2(x-y)+6x(y-x) 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) (2x-3y)-(5x-y) (2X-3y)-(5x-y) (2x-5y)(3x+y) (2x+y)²+(x+3y)(x-3y)-x(5x+8y)因式分解 因式分解(x-2y)(x-3y)+(x-4y)(x-5y)+（x-3y)(x-5y)+(x-2y)(x-4y) x(x-y)2-(y-x)3 因式分解 x-xy+3y-3x 2x+xy-y-4x+5y-6 3x+5y-(x+y)=6 2(x+y)-3x=-7 [2/3x-2/x+y(x+y/3x-x-y)]/x-y/x