题目
题型:不详难度:来源:
n+1 |
n |
1 |
n |
3 |
2 |
1 |
2 |
答案
n+1 |
n |
1 |
n |
1 |
n+1 |
1 |
n |
那么其面积为Sn=
1 |
2 |
1 |
n+1 |
1 |
n |
1 |
2n2+2n |
因此当n=1时,S1=
1 |
2+2 |
1 |
4 |
S1+S2+S3+…+Sn
=
1 |
4 |
1 |
12 |
1 |
24 |
1 |
2n(n+1) |
=
n+1 |
n |
1 |
n |
3 |
2 |
1 |
2 |
n+1 |
n |
1 |
n |
1 |
n+1 |
1 |
n |
1 |
2 |
1 |
n+1 |
1 |
n |
1 |
2n2+2n |
1 |
2+2 |
1 |
4 |
1 |
4 |
1 |
12 |
1 |
24 |
1 |
2n(n+1) |