x²-4x+y²+6y+(√2-3)+13=0 ,求(xy)²=?
已知2X-3√xy-2y=0(x>0)求2x²+xy-9y²分之x²+4xy-16y
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
已知|x²-2xy-8y²|+2√x²-4xy+4y²-1=0,求3x+6y的值
2x+y=0,求4x²+2xy(x+y)+y³
x²-4x+y²+6y+(√2-3)+13=0 ,求(xy)²=?
已知x,y满足x²+y²-4x-6y+13=0,求(- y/x^3)^3÷(- 1/xy)^4.(x
已知x²+y²-2x+4y+5=0,求X^4-y^4/2x^2+xy-y²·2x-y/xy
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
2x²-3xy=y²=0(x,y不得o)求x/y+y/x
已知X²+Y²+X²Y²-4XY+1=0 求:(X-Y)^2008-(XY)^2
已知x/y=2,求x²-xy+3y²/x²+xy+6y²的值
3x+4y=0 x不等于0 求分式2xy+y²/x²-xy