\"\"

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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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Here \"\" and \"\".

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\"\"

\

\"\"

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\"\"

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\"\"

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\"\".

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\"\".

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Therefore, the series \"\" is diverges by using ratio test.\"\"

\

The series \"\" is diverges by using ratio test.