Taylor/Maclaurin series problem

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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.
 
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\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
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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