1/3x-[1/2y-3(x-1/2y)]化简
已知x-y=1,y≠0,求{(x+2y)²+(2x+y)(x+4y)-3(x+y)(x-y)}÷y的值.
化简(2x-3y)(3x-2y+1)
化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1
化简:(x+y)+(2x+y/1*2)+(3x+y/2*3)+...+(9x+y/8*9)
先化简,再求值:x²/x-y-y²/x-y,其中x=1+2又根号3
因式分解 (1)6(x-y)^3-3y(y-x)^2 (2)x(x-y)(a-b)-y(y-x)(
已知:3x=8y.求(1)x+y/y (2)2x+3y/x-2y
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
3y/2x+2y+2xy/x²+xy 2x/x²-64y²-1/x-8y (1/a+1/b
先化简再求值:-3(2x-y)-{7-〔6x+2y-(10x-8y)〕+x-2(3x-4y)}已知x=-1/5,y=-5
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
计算:(1)2/(x+y)+4y/x²-y²(2)x²/x+y-x+y