(-1)^2n+(-1)^2n+1+(-1)^2n+2 n为正整数

来源:学生作业帮助网 编辑:作业帮 时间:2024/07/31 20:36:29
(-1)^2n+(-1)^2n+1+(-1)^2n+2 n为正整数
x)5Ԍ3ӆцpBޓ]lgS7$铠ZΆT_,_ XqP\ [jul,| (4r-󁢄|5562m @g}

(-1)^2n+(-1)^2n+1+(-1)^2n+2 n为正整数
(-1)^2n+(-1)^2n+1+(-1)^2n+2 n为正整数

(-1)^2n+(-1)^2n+1+(-1)^2n+2 n为正整数

2n是偶数,2n+1是奇数,2n+2是偶数
∴偶次幂是正的,奇数次幂是负的
(-1)^2n+(-1)^2n+1+(-1)^2n+2
=1-1+1
=1