Taylor/Maclaurin series problem

  • Thread starter Thread starter ThirdEyeBlind
  • Start date Start date
  • Tags Tags
    Series
Click For Summary

Homework Help Overview

The problem involves using series to approximate the integral of arctan(x^2) from 0 to 1/10 and determining the error bound for this approximation.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to manipulate the Maclaurin series for arctan(x^2) and expresses uncertainty about how to proceed with the integration of the series. Some participants suggest using properties of integrals and series to facilitate the calculation.

Discussion Status

Participants are exploring the integration of the series and discussing the correctness of their approaches. Some have proposed a potential solution and are questioning the validity of their error bound calculations, indicating a productive exchange of ideas without reaching a consensus.

Contextual Notes

There are indications of difficulties with formatting mathematical expressions, and participants are navigating the constraints of homework guidelines while discussing error bounds and series convergence.

ThirdEyeBlind
Messages
9
Reaction score
0

Homework Statement


Use series to show that the integral from 0 to 1/10 of arctan (x^2)dx is approx. 1/3000. What bound can you place on the error in this approximation?


Homework Equations





The Attempt at a Solution


Manipulated Maclaurin series to get the sum from n=0 to infinity of (-1)^n ((x^2)^(2n+1)) / 2n+1
1HPon.gif

Simplify to get
ldIS0.gif
. Now I don't know to take the integral of
ldIS0.gif
, assuming that is the correct way to proceed.
 
Physics news on Phys.org
\int dx \left(\sum\limits_k f(x,k) \right) = \sum\limits_k \int dx f(x,k)

Does that help?
 
[STRIKE]I couldn't get Latex to correctly show what I have so I did it in paint. Is this correct? If it is, how do I evaluate this? Any help would be appreciated.
[/STRIKE]

EDIT: I think I figured it out. tan^-1 (x^2) = x^(2) - x^(6)/3 + x^(10)/5 -... and if you integrate the first term from 0 to 1/10, you get x^3 / 3 which is .1^(3) / 3 which equals 1/3000
EDIT2: For the error bound, is the |error| less than or equal x^7 / 21 -> (1/10)^7 / 21 since the alternating series test applies?
 
Last edited:
ThirdEyeBlind said:
[STRIKE]I couldn't get Latex to correctly show what I have so I did it in paint. Is this correct? If it is, how do I evaluate this? Any help would be appreciated.
[/STRIKE]

EDIT: I think I figured it out. tan^-1 (x^2) = x^(2) - x^(6)/3 + x^(10)/5 -... and if you integrate the first term from 0 to 1/10, you get x^3 / 3 which is .1^(3) / 3 which equals 1/3000
EDIT2: For the error bound, is the |error| less than or equal x^7 / 21 -> (1/10)^7 / 21 since the alternating series test applies?

I'm no expert on errors and stuff, but i think it's correct
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 6 ·
Replies
6
Views
2K
Replies
14
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 6 ·
Replies
6
Views
3K