1 |
1×3 |
1 |
3×5 |
1 |
5×7 |
1 |
2 |
1 |
3 |
1 |
3 |
1 |
5 |
1 |
5 |
1 |
7 |
1 |
2 |
6 |
7 |
3 |
7 |
(2)原式=
1 |
2 |
1 |
3 |
1 |
3 |
1 |
5 |
1 |
2n−1 |
1 |
2n+1 |
1 |
2 |
2n+1−1 |
2n+1 |
n |
2n+1 |
故答案是
3 |
7 |
n |
2n+1 |
1 |
1×3 |
1 |
2 |
1 |
3 |
1 |
3×5 |
1 |
2 |
1 |
3 |
1 |
5 |
1 |
5×7 |
1 |
2 |
1 |
5 |
1 |
7 |
1 |
1×3 |
1 |
3×5 |
1 |
5×7 |
1 |
1×3 |
1 |
3×5 |
1 |
5×7 |
1 |
(2n−1)(2n+1) |
1 |
1×3 |
1 |
3×5 |
1 |
5×7 |
1 |
2 |
1 |
3 |
1 |
3 |
1 |
5 |
1 |
5 |
1 |
7 |
1 |
2 |
6 |
7 |
3 |
7 |
1 |
2 |
1 |
3 |
1 |
3 |
1 |
5 |
1 |
2n−1 |
1 |
2n+1 |
1 |
2 |
2n+1−1 |
2n+1 |
n |
2n+1 |
3 |
7 |
n |
2n+1 |