解方程组:x+y+xy=11 x2y+xy2=30,快
数学竞赛题:若实数x,y满足方程组xy+x+y+7=0,3x+3y=9+2xy,则x2y+xy2=?
已知x+y=-5,xy=7,求x2y+xy2-x-y的值.
已知x+y=6,xy=-3,则x2y+xy2=
若x+y=2,xy=-4,求x2y+xy2+1的值
已知x+y=6,xy=4,则x2y+xy2的值为______.
已知x+y=10,xy=24,求x3+y3-x2y-xy2的值
x+y=5,xy=2,求代数式-x2y-xy2的值
若x+y=5,xy=6,则x2y+xy2的值为______.
若x-y=3,xy=-2,则xy2-x2y的值是______.
已知x,y是正整数,且xy+x+y=23,x2y+xy2=120,求x,
先化简,后求值.[2x(x2y-xy2)+xy(xy-x2)]÷x2y,其中x=2013,y=2012.
已知实数x、y满足x+y+xy=9,x2y+xy2=20,求x2+y2的值.