\"\"

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The series is \"\".

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Ratio Test :

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(i) If \"\", then the series is \"\" is absolutely convergent.

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(ii) If \"\" or \"\", then the series is \"\" is divergent.

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(iii) If \"\", then the ratio test is inconclusive.

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\"\"

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As \"\", \"\".

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\"\"

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Since \"\", then the ratio test is inconclusive.

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So apply any alternate method to test the convergence of the series.

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\"\"

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Now check the convergence of \"\" using alternate series test.

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Alternating series test :

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Suppose we have the series \"\" such that \"\" or \"\" where \"\" for all values of \"\".

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Then if the following two conditions are satisfied the series is convergent.

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(1) \"\" is a decreasing sequence.

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(2) \"\".

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Condition 1 : 

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\"\".

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The value of \"\" decreases as the denominator increases.

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Condition 2 :

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\"\".

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Hence the series is convergent by alternate series test.

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\"\"

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The series \"\" is conditionally convergent.