Finite arithmetico–geometric series sum (Sum of (linear in k) times geometric weight; use r≠1 formula or)
jee-mainjee-advanced
Sum of (linear in k) times geometric weight; use r≠1 formula or multiply–subtract trick
What each symbol means
| Symbol | What it stands for |
|---|---|
| n | Number of terms |
| r | Common ratio |
| a,d | AP parameters |
When to use this
r ≠ 1; if r=1 reduces to sum of AP = n/2(2a+(n−1)d).