Find the sum of the following geometric progressions :
2, 6, 18, … to 7 terms
Common Ratio = r =
∴ Sum of GP for n terms = …(1)
⇒ a = 2, r = 3, n = 7
∴ Substituting the above values in (1) we get
⇒
⇒ 37 – 1
⇒ 2186