1\x+1\y=8\x+y,则y\xy+x\xy=?

1\x+1\y=8\x+y,则y\xy+x\xy=? xy-1+x-y 已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y= 若x+y=-1,则x^4+5x^3y+x^2y+8x^2y^2+xy^2+5xy^3+y^4=( ) 已知xy>0,证明xy+xy/1+x/y+y/x>=4 已知x+y=1,xy=1/5,则x^2y=xy^2 xy/3x+2y=1/8 xy/2x+3y=1/7 已知x+y=3,xy=1,则4x+3xy+4y= 若x-y=1,xy=5,则x²y-xy²=? 已知实数x、y满足xy>0,且8/xy+1/x+1/y=1, x^=2-xy y^=1-xy 则x^-y^ 多少啊 设X,Y属于正实数,xy-(x+y)=1,则x+y最小值