Deriving the Power Series of Arctan through Integration

In summary, to get the power series of arctan using integration, we can use the Taylor series of \frac{1}{1+x^2} and the derivative of arctan x to find the coefficients of the power series. This involves understanding Taylor series and their usage.
  • #1
hivesaeed4
217
0
How do we get the power series of arctan using integration. Could someone explain this step by step as I'm quite confused about it.
 
Physics news on Phys.org
  • #2
hivesaeed4 said:
How do we get the power series of arctan using integration. Could someone explain this step by step as I'm quite confused about it.


[itex]\frac{1}{1+x^2} = 1-\frac{x^2}{2!}+\frac{x^4}{4!}-...[/itex], and since

[itex](Arctan\, x)'=\frac{1}{1+x^2}[/itex] , then...

DonAntonio
 
  • #3
hivesaeed4 said:
How do we get the power series of arctan using integration. Could someone explain this step by step as I'm quite confused about it.

Hey hivesaeed4 and welcome to the forums.

To add on to what DonAntonio said, investigate what Taylor series are and how are they are used:

http://en.wikipedia.org/wiki/Taylor_series
 
  • #4
Thanks. Thanks alot.
 

1. What is the power series representation of arctan?

The power series representation of arctan is:
arctan(x) = x - (x^3)/3 + (x^5)/5 - (x^7)/7 + ... + (-1)^n * (x^(2n+1))/(2n+1) + ...

2. What is the interval of convergence for the power series of arctan?

The interval of convergence for the power series of arctan is -1 < x < 1, which means that the series will converge for any value of x within this interval and diverge for any value of x outside of this interval.

3. How accurate is the power series representation of arctan?

The accuracy of the power series representation of arctan depends on the value of x and the number of terms used in the series. Generally, the more terms used, the more accurate the approximation will be.

4. Can the power series of arctan be used to calculate the exact value of arctan(x)?

No, the power series representation of arctan is an infinite series and can only provide an approximation of the exact value of arctan(x). However, the more terms used in the series, the closer the approximation will be to the exact value.

5. What is the relationship between the power series of arctan and the power series of tan?

The power series of arctan and the power series of tan are inverse functions of each other. This means that the power series of arctan can be obtained by replacing x with 1/t in the power series of tan, and vice versa.

Similar threads

Replies
5
Views
2K
Replies
2
Views
2K
Replies
5
Views
1K
Replies
3
Views
980
Replies
2
Views
789
Replies
14
Views
2K
  • Calculus
Replies
9
Views
1K
  • General Math
Replies
7
Views
1K
Back
Top