Question

我是一名5年级的学生,遇到这三道题不懂,爸妈不在家,所以请求大家.

Answer 1

1.nth n*(-1)^n

10th = (-1)^10*10=10

100th=100

301th=-301

2.nth 2n*(-1)^n

10th =20

100th=200

301th=-602

3.nth (n+2/n)*(-1)^n+1

10th =-12/10

100th=-102/100

301th=303/301