Saved Bookmarks
| 1. |
The sums of first n terms of three arithmetic progressions are S1, S2 and S3 respectively. The first term of each A.P. is 1 and their common difference are 1, 2 and 3 respectively. Prove that S1+S3=2S2. |
| Answer» The sums of first n terms of three arithmetic progressions are S1, S2 and S3 respectively. The first term of each A.P. is 1 and their common difference are 1, 2 and 3 respectively. Prove that S1+S3=2S2. | |