问题 填空题

计算:5x(x2-2x+4)+x2(x-1)

答案

解: 5x(x2-2x+4)+x2(x-1)

=(5×1)·x·x2-(5×2)·x·x+(5×4)·x+x2·x-(1×1)x2

=5x3-10x2+20x+x3-x2

=6x3-11x2+20x

单项选择题
多项选择题