问题 填空题

已知x+y=3,x2+y2-xy=4,那么x4+y4+x3y+xy3的值为______.

答案

∵x+y=3,x2+y2-xy=4,

∴x4+y4+x3y+xy3

=x3(x+y)+y3(x+y),

=(x3+y3)(x+y),

=(x+y)(x2+y2-xy)(x+y),

=32×4,

=36.

故答案为:36.

单项选择题
多项选择题