化简(1)(-2x^1/4y^-1/3)(3x^1/2y^2/3)
化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1
(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
因式分解 (1)6(x-y)^3-3y(y-x)^2 (2)x(x-y)(a-b)-y(y-x)(
计算:1/(x-y)-1/(x+y)-2y/(x^2+y^2)-4y^3/(x^4+y^4)-8x^7/(x^8+y^8
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
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
化简:(x+y)+(2x+y/1*2)+(3x+y/2*3)+...+(9x+y/8*9)
已知:3x=8y.求(1)x+y/y (2)2x+3y/x-2y
化简,并求值2(x-2y)²-4(x+3y)(x-3y)-2(x-y).(y+x)-5(-x-1)²
(3x-y)^2+(3x+y)(3x-y),x=1,y=-2
[(2x+y)^2+(y+2x)(y-2x)-2y(4x-y)]/4y,其中x=1/2,y=1/3