问题 解答题
计算下列各题
(1)x2(x-1)-2x(x2-2x+3)
(2)
252×4-242×4
答案

(1)x2(x-1)-2x(x2-2x+3)

=x3-x2-2x3+4x2-6x                                          

=-x3+3x2-6x.

(2)原式=

4×(25+24)×(25-24)

=

4×49×1

=14.

问答题 简答题
多项选择题