3X+3Y/X^2-Y^2为什么等于3/X-Y
3X+3Y/X^2-Y^2为什么等于3/X-Y
若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于
已知 2x-3y/y等于2 求x-y/2x 求x-3y/2x+y
为什么|x-y+3|+(x+y-1)^2等于|x-y+3|+(x+y)^2-2x-2y+1?
(x-2y)2+(x+2y)(x-2y)-(x-3y)(x-y)计算结果是什么?x等于-4,y等于0.5代入后是多少第一
[(3x+y)(x-y)-(2x+3y)(x-y)]*(x-y)
化简:(x-3y)(x+y)-(x-2y)(x+2y)-(x-y)平方
【x-3y][x+y]-[x-2y][x +2y]-[x-y
有这样一道题:"计算(2*x*x*x-3*x*x*y-2*x*y*y)-(x*x*x-2*x*y*y+y*y*y)+【-
(3x-5y)-(3x-2y)等于几
2(x+y)的平方-3x-3y-2等于0,x+y等于多少?
(3x-y)(x+2y)最后等于多少!