SOLUTION: find the sum of the first 12 terms of the geometric sequence 2,6.18.54

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Question 905004: find the sum of the first 12 terms of the geometric sequence 2,6.18.54
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
r = 3
sum%28+a%5Bi%5D%2C+i=1%2C+n+%29+=+a%5B1%5D%28%281-r%5En%29%2F%281-r%29%29
sum%28+a%5Bi%5D%2C+i=1%2C+12+%29+=+2%28%28-531440%29%2F%28-2%29%29 = 531,440