2 |
an+1an |
n(a1+an) |
2 |
n(1+2n-1) |
2 |
2 |
an+1an |
2 |
(2n+1)(2n-1) |
1 |
2n-1 |
1 |
2n+1 |
1 |
3 |
1 |
3 |
1 |
5 |
1 |
2n-1 |
1 |
2n+1 |
1 |
2n+1 |
2n |
2n+1 |
A.11 | B.12 | C.13 | D.14 |
A.65 | B.70 | C.130 | D.260 |
2n |
3 |
4 |
9 |
1 |
2 |
A.182 | B.242 | C.273 | D.484 |
lim |
n→∞ |
nan |
S2n |
A.
| B.
| C.1 | D.2 |
© 2017-2019 超级试练试题库,All Rights Reserved.