化简:2x·4y+4y
化简:(2x-y)²-4(x-y)(x+y)
化简:{(x+2y)(2y-x)-4y(-x+y) } / (-2x)
[(x+2y)^2-(x-2y)^2-(x-2y)(x+2y)-4y^2]/2x 化简
化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1
{(z+y)(x-y)-(x-y)的2次方+2y(x-y)}除以4y
x^2-y^2/x+y-4x(x-y)+y^2/2x-y,
化简:[(2x-y)平方+(2x+y)(2x-y)-4x(x-y+1)]÷2x
x+2y+4y^2/x-y+4x^y/4y^2-x^2
(2x-y)^2-4(x-y)(x+2y)
(2x-y)²-4(x-y)(x+2y)
化简(2x^3y^3+x^4y^2+x^2y^4)^2-x^2y^2(x+y)^2,x=2012,y=-2011
化简(x+y)-(2x+y/2)-(3x+y/6)-(4x+y/12)-(5x+y/20)-……-(10x+y/90)