Approximating Infinite Series: Calculating Sum and Estimating Error

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Homework Help Overview

The discussion revolves around approximating the sum of an infinite series defined as (4-sin(n))/(n^2 + 1) starting from n=1. Participants are tasked with calculating the sum of the first five terms and estimating the tail of the series from n=6, while also considering error estimation.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • The original poster attempts to prove convergence by comparison to a known convergent series and calculates the first five terms. Questions arise regarding the calculation of the tail and the associated error. Some participants express confusion about the relationship between the tail and the error, while others question the validity of the maximum error estimation.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the tail and error concepts. Some guidance has been offered regarding the relationship between the tail and maximum error, but there is no explicit consensus on the methods for calculating these values.

Contextual Notes

Participants are operating under the constraints of homework rules, which may limit the information they can use or the methods they can apply. There is uncertainty regarding the accuracy of the maximum error estimation and the appropriate approach for calculating the tail.

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Homework Statement


The infinite Series starts at n=1 and is (4-sin(n))/(n^2 + 1)

For each series which converges, give an approximation of its su, together with an error estimate, as follows. First calculate the sum s_5 of the first 5 terms, Then estimate the "tail" which is the infinite series starting at n=6 by comparing it with an appropiate improper integral or geometric series.

Homework Equations


The Attempt at a Solution



Ok, so to start off I proved it converges by comparing it to 5/n^2 since this series is larger then the original one and it converges by the p-series test then the original series also converges. I calculated the first five sums and got 2.863 for my s_5 I'm unsure of how to calculate the tail however, and unsure of how to calculate the error. At first I was thinking to do the improper integral from 6 to infinite of 5/(n^2) since I compared it to this before, but with that I got .8 and that seemed large for the tail of this series. I am also unsure of how to find the error? I was thinking that once i find the value of the tail that the value of (s_5 + tail) - (s_5) would be the error? I don't really know. Please help thanks!
 
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I vaguely remember posting to the same question a few days ago. Was my maximum error just too high?
 
I saw this but I just don't understand how you actually found the error...
 
are the tail value and the error the same thing?
 
The maximum tale value is the maximum error, yes.
 

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