Approximating Infinite Series: Calculating Sum and Estimating Error

In summary, the problem involves finding the sum and error estimate for an infinite series. The series starts at n=1 and is (4-sin(n))/(n^2 + 1). To prove convergence, the series is compared to 5/n^2. The first five terms are calculated and the sum s_5 is found to be 2.863. The "tail" of the series, starting at n=6, is approximated by comparing it to an appropriate improper integral or geometric series. The maximum error is found by comparing the tail value to the sum s_5.
  • #1
physstudent1
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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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  • #2
I vaguely remember posting to the same question a few days ago. Was my maximum error just too high?
 
  • #3
I saw this but I just don't understand how you actually found the error...
 
  • #4
are the tail value and the error the same thing?
 
  • #5
The maximum tale value is the maximum error, yes.
 

1. What is an infinite series?

An infinite series is a sum of an infinite number of terms. These terms can either be numbers or functions.

2. Why is approximating infinite series important in science?

Approximating infinite series is important because it allows us to make complex calculations more manageable. It also helps us understand the behavior of functions and make predictions based on the series' properties.

3. How do you approximate an infinite series?

There are several methods for approximating infinite series, including the partial sum method, the comparison test, and the ratio test. These methods involve finding a finite sum that closely approximates the infinite sum.

4. Can an infinite series have a definite value?

Yes, some infinite series have a definite value, while others are divergent and do not have a finite sum. The value of an infinite series can be determined by using one of the approximation methods.

5. In what fields of science is approximating infinite series commonly used?

Approximating infinite series is commonly used in fields such as physics, engineering, and finance. It is also used in computer science and data analysis to approximate complex functions and make predictions based on data sets.

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