determine if the series converge or diverge using an appropiate test.
∞
? 2^n - 5^n+1
n=1 6^n


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I will show that the series converges by the integral test :


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We thus have the integral converges . We therefore have by the integral test that the series also

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We also have :
The series is thus the sum of three geometric series which converge :

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and

; so , the series converges to :

.

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and

; so , the series converges to :

.

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and

; so , the series converges to :

. We thus have the series is the sum of three convergent geometric series :