SOLUTION: find the sum of the first 12 terms of the geometric sequence 2, 6, 18, 54,....

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Question 976000: find the sum of the first 12 terms of the geometric sequence 2, 6, 18, 54,....
Answer by Iambibek1(1) About Me  (Show Source):
You can put this solution on YOUR website!
Here,
1st term(a)=2
common ratio(r)=t2/t1=3
So,We have,
Sn=a(r^(n-1))/(r-1)
S12={2(3^(12-1)}/(3-1)
By solving this we can get sum of 12 terms=3^11