已知:(x+2)²+|x+y-2|=0,求3x²y+{-2x²y-[-2xy+(x
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
已知实数x,y满足x²+y²-xy+2x-y+1=0 求x y
已知x-3y=0,求2x+y/x²-2xy ×(x-y)的值
已知x-3y=0,求(x²-2xy+y²/x-y)-2y的值
已知x²+y²-2x+4y+5=0,求X^4-y^4/2x^2+xy-y²·2x-y/xy
已知y-2x=0,求代数式(x²-y²)(x²-xy+y²)/(x²+
2x²-3xy=y²=0(x,y不得o)求x/y+y/x
已知(x+3)+丨X-y+10丨=0 ,求5x²y-[2x²y-(3xy-xy²)-3x&
已知:(x+2)²+|x+y-2|=0,求3x²y+{-2x²y-[-2xy+(x
已知X²+Y²+X²Y²-4XY+1=0 求:(X-Y)^2008-(XY)^2
已知x/y=3,求x²+2xy-3y²/x²-xy+y²
已知y分之x=3,求x²-xy+y²分之x²+2xy-3y²