3×[(3x-2y)+(x-3y+1)]-2×[2×(3x-2y)-(x-3y+1)]等于几
3×[(3x-2y)+(x-3y+1)]-2×[2×(3x-2y)-(x-3y+1)]等于几
为什么|x-y+3|+(x+y-1)^2等于|x-y+3|+(x+y)^2-2x-2y+1?
已知x+y+2(-x-y+1)=3(1-y-x)-4(y+x-1),则x+y等于( )
已知:3x=8y.求(1)x+y/y (2)2x+3y/x-2y
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
(x-y)(x-2y)-(3x-2y)(x-3y)
1.((y+2x)(-2x+y)+4(x+2y)^2)/3y 2.(2(x-y)^3-8(x-y)^2(x+y)+6y(
全集U等于{(x,y)/x,y属于实数}A等于{(x,y)/x减2分之y减3等于1}B等于{(x,y)/y等于x加1}求
(3x-5y)-(3x-2y)等于几
(x-y)的3次幂乘(x-y)的2次幂乘(y-x)等于?
2(x-y)+3(x+y)2-5(x-y)-8(x+y)2-(x-y)