Determine if the series sum_{n=0}^infty a_n is convergent or divergent if the partial sum of the n terms of the series is given below. If the series is convergent, determine the value of the series. S_n=frac{5+8n^2}{2-7n^2}

mattgondek4

mattgondek4

Answered question

2020-11-23

Determine if the series n=0an is convergent or divergent if the partial sum of the n terms of the series is given below. If the series is convergent, determine the value of the series.
Sn=5+8n227n2

Answer & Explanation

krolaniaN

krolaniaN

Skilled2020-11-24Added 86 answers

Result on convergence of series:
If the sequence of partial sum Sn=a1+a2++an of given series n=0an is convergent sequence them the series is also convergent .
Moreover, the sum of the series is given by
n=0an=limnSn
Now, the given sequence of partial sum is
Sn=5+8n227n2
Writing the first few terms of the sequence,
<5+827,5+8×2227×22,5+8×2327×23,>
<2.6,1.42,1.26,>
Clearly, the sequence is monotonically increasing.
Also it is bounded above by'0' that is Sn<0,n,
Hence, the given sequence of partial sum is convergent.
In order to get the sum of the series, we will find the limit of the given sequence of partial sum.
limnSn=limn5+8n227n2
limnSn=limn16n14n
=87
Hence,
n=0an=limnSn=limn5+8n227n2=87

Jeffrey Jordon

Jeffrey Jordon

Expert2022-01-14Added 2605 answers

Answer is given below (on video)

Do you have a similar question?

Recalculate according to your conditions!

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?