FIND THE SUM OF THE SERIES  2+6+ +18 +.......... + 4374 .

above sequence is a gp with common ratio=3

last term =4374=ar^n-1

sum = a(rⁿ-1)/(r-1)

=(arⁿ-a)/2

=(ar^n-1.r-a)/2

=(4374.3-2)/2

= 6560