若(|x+1|+|x-2|)(|y+1|+|y-3|)
1、x(x-y)(x+y)-x(x+y)^2
若变量x,y满足约束条件{x>=-1;y>=x;3x+2y
若x=-1/4,能否确定代数式(2x-y)(2x+y)+(2x-y)(y-4x)+2y(y-3x)的值?
若全集I={(x,y)|x,y∈R},集合M={(x,y)|(y-3)/(x-2)},N{(x,y)|y=x=1},则(
因式分解 (1)6(x-y)^3-3y(y-x)^2 (2)x(x-y)(a-b)-y(y-x)(
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
(1)(x^2/x)-y-x-y
(3x-y)^2+(3x+y)(3x-y),x=1,y=-2
(x+2)(x+3) (x-4)(x+1) (y+4)(y-2) (y-5)(y-3)
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值
若x,y∈{-√3,-1,1,2},则(x,y)∈{(x,y)|x^2+y^2