堆排序大顶堆:分解因式:a的五次方+a+1

来源:百度文库 编辑:高考问答 时间:2024/04/26 23:55:34
一道数学竞赛题……
寒假作业,急需答案!!!!!!!!

a^5+a+1
=a^5-a^2+a^2+a+1
=a^2×(a^3-1)+(a^2+a+1)
=a^2×(a-1)(a^2+a+1)+(a^2+a+1)
=(a^2+a+1)[a^2×(a-1)+1]
=(a^2+a+1)(a^3-a^2+1)

a^2表示a的平方
a^3,a^4,a^5也是表示幂

假定:a^5 + a + 1 = (a^3 + x1*a^2 + x2*a + 1)(a^2 + x3*a + 1),则有待定参数关系:

x1 + x3 = 0 ....................(1)
x2 + x1*x3 + 1 = 0 .............(2)
1 + x2*x3 + x1 = 0 .............(3)
x3 + x2 = 1 .....................(4)

解得:
x1 = -1、x2 = 0、x3 = 1
a^5 + a + 1 = (a^3 - a^2 + 1)(a^2 + a + 1)

x1 = 2、x2 = -1、x3 = -2
a^5 + a + 1 = (a^3 + 2a^2 - a + 1)(a^2 - 2a + 1)

都是高手,但我还是偏向于添项法!这种题一般都使用添项法