(3x+2y)^2-9(x-y)^2(18x^2-12xy+2y^2)/(3x-y)

x²/xy-x/y 3x/4x+y - x-2y/4x+y (1-y/y+x)÷x/y²-x² x(x-y)2-(y-x)3 9y=3x-(x-1),4(x+y)-(2x+4)=8y [(1/9(x+y)^3-2(x+y)^2-2/3(x+y)]÷x+y/3x+y/3x+y是整体.. 9xy(x-y)(x+1)-3y(x-y)(3x+2y)+6y的平方(x-y)(x+1),因式分解 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 [2/3x-2/x+y(x+y/3x-x-y)]/x-y/x 化简：{2/3x-2/(x+y)[(x+y)/3x-x-y]}/(x+y)/x 计算2/3x-2/x+y(x+y/3x-x-y)/x-y/x [(-x-y)(-x+y)-(x+y)^2-x(y-y^2)}÷1/2y 化简3x-2/(x+y)[(x+y)/3x-x-y]÷(x-y)/x (3x-y)^2+(3x+y)(3x-y),x=1,y=-2 3(x+y)-2(x-y)=11 4(x+y)+3(x-y)=9 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 81/8*(-x-y)^6*(x-y)^3*4/9(x+y)^4*(y-x)^2 计算(x-y)^7÷(y-x)^6+9-x-y)^3÷(x+y)^2 二元一次方程 ：2(x+y)-(x-y)=3 (x+y)-2(x-y)=1 (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5)