\"\"

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Alternating Series Test :

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If the alternating series \"\" satisfies

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(i)  \"\",

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(ii) \"\", then the series is convergent.

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\"\"

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The series is \"\".

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Since the series is alternating, verify condition (i) and (ii) of the Alternating Series Test.

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It is not obvious that the sequence given by \"\" is decreasing.

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So consider the related function \"\".

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Differentiate the function with respect to x .

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\"\"

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If the function is decreasing, then \"\".

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\"\"

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\"\"

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\"\"

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Thus, \"\" is decreasing on the interval \"\".

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This means that, \"\" and therefore, \"\", when \"\".

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The inequality \"\"can be verified directly but all that really matters is that the sequence \"\" is eventually decreasing.

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Thus, condition (i) verified.

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\"\"

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\"\"

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Apply L hospital rule :

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\"\"

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As \"image\", then \"image\".

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\"\"

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\"\".

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Thus, condition (ii) is verified.

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Thus the given series is convergent by the Alternating Series Test.

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\"\"

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The series \"\" is convergent.