# ISI2015-DCG-19

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The expression $3^{2n+1} + 2^{n+2}$ is divisible by $7$ for

1. all positive integer values of $n$
2. all non-negative integer values of $n$
3. only even integer values of $n$
4. only odd integer values of $n$

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1 vote

Option (A) is the correct answer.

0

if you put n=0, then also it is divisible by 7.

So, the answer will be:- B.all non-negative integer values of n

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