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Please solve this question for me Note: the value of p=2

Please solve this question for me Note: the value of p=2-example-1

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Given:


\sum_{n\mathop{=}1}^(\infty)((np)^(-2))/((2)/(n^2)+(3)/(n)+1)

Find-:

Find the formula for n partial sum, and determine whether the series converges or diverges.

Explanation-:

The value is:


\begin{gathered} =\sum_{n\mathop{=}1}^(\infty)((np)^(-2))/((2)/(n^2)+(3)/(n)+1) \\ \\ =\sum_{n\mathop{=}1}^(\infty)(1)/(n^2p^2((1)/(n^2)+(3)/(n)+1)) \\ \\ =\sum_{n\mathop{=}1}^(\infty)(1)/(p^2((n^2)/(n^2)+(3n^2)/(n)+n^2)) \\ \\ =\sum_{n\mathop{=}1}^(\infty)(1)/(p^2(1+3n+n^2)) \end{gathered}

So, the value is,


=(1)/(p^2)\sum_{n\mathop{=}1}^(\infty)(1)/(n^2+3n+1)

Apply telescoping series


\sum_{n\mathop{=}1}^(\infty)(1)/(n^2+3n+1)=(1)/(2)

The value is:


\begin{gathered} =(1)/(p^2)*(1)/(2) \\ \\ =(1)/(2p^2) \end{gathered}

It is a series of converges.


\begin{gathered} =(1)/(2p^2) \\ \\ =(1)/(2(2)^2) \\ \\ =(1)/(2*4) \\ \\ =(1)/(8) \end{gathered}

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