(2xy/x2-y2)+(x+y/x)-(y/y-x)
正整数x,y满足x2-y2=2xy,求x-y/x+y的值
整数x,y满足x2-y2=2xy,求x-y/x+y的值
正数xy满足x2-y2=2xy,求x+y分之x-y的值
x2-xy-2y2-x+5y-2
x2-2xy+y2+3x-3y+2.
x2-xy-2y2-x+5y-2因式分解
因式分解 x2+xy-2y2-x+7y-6
2x2+xy-3y2+x+4y-1因式分解
已知2x=3y,求xy/(x2+y2)-y2/(x2-y2)的值
若x2-2xy-y2-x+Y-1=0 求x-y的值
已知实数x、y满足2x2-7xy+3y2=0,求x:y
X2+y2+2xy+x-y=0,求x的最大值及y的最小值