please answer it guys
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Answer:
nth term = 4×(3)^n-1
Step-by-step explanation:
Given S n = 2(3^n -1)
for n =1, S1 = first term = t1 =2(3-1) =4
for n= 2 , S2 = the sum o f first two terms = 2(9-1) =16
now t2 = S2 -S1 =16- 4 =12
similarly S3 = 2(26) =52
and t3 = S3 -S2 =52 -16 = 36 and so on
Now we can write the series as 4,12,36,...
with a common ratio 3. ∴ the sequence is in G.P
now the nth term can be written as a×r^(n-1), where 'r' is the common ratio and 'a' is the first term .
nth term = 4×(3)^n-1
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