14.已知x、y均为实数,且满足xy+x+y=17,x2y+xy2=66,求x4+x3y+x2y2+xy3+y4的值.已知x、y均为实数,且满足xy+x+y=17,x2y+xy2=66,求x4+x3y+x2y2+xy3+y4的值.

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14.已知x、y均为实数,且满足xy+x+y=17,x2y+xy2=66,求x4+x3y+x2y2+xy3+y4的值.已知x、y均为实数,且满足xy+x+y=17,x2y+xy2=66,求x4+x3y+x2y2+xy3+y4的值.

14.已知x、y均为实数,且满足xy+x+y=17,x2y+xy2=66,求x4+x3y+x2y2+xy3+y4的值.已知x、y均为实数,且满足xy+x+y=17,x2y+xy2=66,求x4+x3y+x2y2+xy3+y4的值.
14.已知x、y均为实数,且满足xy+x+y=17,x2y+xy2=66,求x4+x3y+x2y2+xy3+y4的值.
已知x、y均为实数,且满足xy+x+y=17,x2y+xy2=66,求
x4+x3y+x2y2+xy3+y4的值.

14.已知x、y均为实数,且满足xy+x+y=17,x2y+xy2=66,求x4+x3y+x2y2+xy3+y4的值.已知x、y均为实数,且满足xy+x+y=17,x2y+xy2=66,求x4+x3y+x2y2+xy3+y4的值.
由已知:xy+x+y=17,
xy(x+y)=66,可知xy和x+y是方程t2-17t+66=0的两个实数根,得:t1=6,t2=11.
即xy=6,x+y=11,或xy=11,x+y=6.
当xy=6,x+y=11时,x,y是方程u2-11u+6=0的两个实数根.这时,x2+y2=(x+y)2-2xy=112-2×6=109.
x4+x3y+x2y2+xy3+y4=(x2+y2)2-x2y2+xy(x2+y2)=12499.
当xy=11,x+y=6.x,y是方程u2-6u+11=0的两个实数根.
因为Δ<0,方程无实根.