题目内容
已知Sn,Tn分别是等差数列{an},{bn}的前n项和,且
=
,(n∈N+)则
+
=______.
| Sn |
| Tn |
| 2n+1 |
| 4n-2 |
| a10 |
| b3+b18 |
| a11 |
| b6+b15 |
∵Sn,Tn分别是等差数列{an},{bn}的前n项和,
且
=
,(n∈N+),
∴
+
=
=
=
=
.
故答案为:
.
且
| Sn |
| Tn |
| 2n+1 |
| 4n-2 |
∴
| a10 |
| b3+b18 |
| a11 |
| b6+b15 |
| a10+a11 |
| b10+b11 |
=
| S20 |
| T20 |
| 40+1 |
| 80-2 |
| 41 |
| 78 |
故答案为:
| 41 |
| 78 |
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