为什么|x-y+3|+(x+y-1)^2等于|x-y+3|+(x+y)^2-2x-2y+1?
为什么|x-y+3|+(x+y-1)^2等于|x-y+3|+(x+y)^2-2x-2y+1?
1、x(x-y)(x+y)-x(x+y)^2
已知:3x=8y.求(1)x+y/y (2)2x+3y/x-2y
已知x+y+2(-x-y+1)=3(1-y-x)-4(y+x-1),则x+y等于( )
因式分解 (1)6(x-y)^3-3y(y-x)^2 (2)x(x-y)(a-b)-y(y-x)(
(1)(x^2/x)-y-x-y
1) (x+y)^2-(x+y)^3 2) (x-y)^2-(x-y)^3 3)(x-y)^2-(y-x)^3 因式分解
先化简再求值:(x-2y)²-(x+2y)(x-2y)-(x-3y)(x-y).其中x²+9y
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y
[(-x-y)(-x+y)-(x+y)^2-x(y-y^2)}÷1/2y
若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于
(x-y)的四次方(x-y)-2(x-y)²(y-x)³等于?