Saved Bookmarks
| 1. |
If Sn denotes the sum of the first n termof an AP what will be the value of S2 |
|
Answer» ANSWER s
−2s n−1
+s n−2
=(s n
−s n−1
)−(s n−1
−s n−2
) =a n
−a n−1
[∵(s n
−s n−1
)=a n
] =[a+(n−1)d]−[a+(n−2)d] =a+nd−d−a−nd+2d =d |
|