X2+xy-12y2-2x+27y+5因式分解

X2+xy-12y2-2x+27y+5因式分解 x2-xy-2y2-x+5y-2 x2-xy-2y2-x+5y-2因式分解 2x2+xy-y2-4x+5y-6 因式分解 (x-y)(x2+xy+y2) (x+y)(x2-xy+y2) 已知x2+y2+4x-2y+5=0,求x2+2xy+y2值 4x2-y2/x2-2xy+y2 +(2x-y)/2x2-2xy 计算(x+y/x-y + 4xy/y2-x2)(x2-9y2)/（x2+2xy-3y2） 解方程组 ｛3x2-y2=8 {4x2+12xy+9y2=1 {x2+2xy+y2-4=0 x2+xy+y2=4 4x2-9y2=0 x2-2xy+y2-1=0还有{x2+y2=4xy-y2+4=0x2-----x的平方 y2------y的平方 还有{2x-3y=12x2-3xy+y2-4x+3y-3=0 已知x/y=3/5,求 (x2-xy+2y2)/(x2+2xy-y2)的值 因式分解：3x2+5xy-2y2+x+9y-4 x2+x-(a2-a) 3x2+4xy-y2 x,y,a后面的2表示平方 x2-2xy+y2=4 x2+y2-x-y=6 解不等式x2-2xy+y2=4 x2+y2-x-y=6 解不等式 已知x2+4y2+x2y2+1=6xy,则(x4-y4)/(2x2+xy-y2)*(2x-y)/(xy-y2)/(x2+y2/y)2= 3x2+4xy-y2因式分解2x(x-y)4-x2(x-y)2+xy((y-x)2x3-13x-12x3+2x2+2x+12x3+x2-5x+2 因式分解 2x2+xy-y2-4x+5y-6 x2-y2+a2-b2+2ax+2by 3x2+5xy-2y2+x+9y-4 b4-2b2-82x2+xy-y2-4x+5y-6x2-y2+a2-b2+2ax+2by3x2+5xy-2y2+x+9y-4b4-2b2-8 已知x+y=5,xy=-12,求代数式x2-xy+y2 已知x2+xy=12,xy+y2=15,求(x+y)2-(x+y)(x-y)的值