(3x-y)²-2x(4x-5y)-(x+2y)²
(3x-y)²-2x(4x-5y)-(x+2y)²
(x-2y)²+(2x-4y)(x+y)+(x+y)²
已知x,y为实数,且2(x+2y)=x²+y²+5求代数式3x-4y分之x²+y²
求因式分解(x-y)²-2(x-y)³和(x+y)(x-y)-x(x-y)
计算4(x+y)^5(x-y)^4÷[2(x+y)³*(y-x)²]
(2x-y)²-4(x-y)(x+2y)
(x-y)的四次方(x-y)-2(x-y)²(y-x)³等于?
化简:(2x-y)²-4(x-y)(x+y)
先化简,在求值:(x-y)²+(3x-2y)(2x+y)-x(6x-y)
先化简再求值:(x-2y)²-(x+2y)(x-2y)-(x-3y)(x-y).其中x²+9y
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
1.((y+2x)(-2x+y)+4(x+2y)^2)/3y 2.(2(x-y)^3-8(x-y)^2(x+y)+6y(