What are the complex poles of the function 1/(x^4+1)?

  • Thread starter Thread starter doey
  • Start date Start date
  • Tags Tags
    Integral
doey
Messages
27
Reaction score
0
1. Homework Statement [/b
from -∞ to ∞ of ∫1/(x^4+1) dx

Homework Equations


how can i actually find out the pole of this function


The Attempt at a Solution


i try to determine the pole and x^4=-1,for this i have obtain the root which is (-1)^1/4,but i dun noe how to find out the remaining roots and it really make me confuse for this ==
 
Physics news on Phys.org
Since x4+1 = 0 has no real-valued solutions, your function f(x) = 1/(x4+1) has no poles. You'll need a different approach for this integral.
 
Michael Redei said:
Since x4+1 = 0 has no real-valued solutions, your function f(x) = 1/(x4+1) has no poles. You'll need a different approach for this integral.

There are complex poles. There are four of them. Write the root in polar form r e^{i \theta} and try and figure out what the possibilities are for r and \theta.
 
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...
Back
Top