# Thread: Quick Residue theorem question

1. ## Quick Residue theorem question

I just have a quick question on a problem in the text book,

Determine the singular points of:

1/(z^3+i)

Am i right in assuming there are only 2 singular point, z=(-i)^1/3 and z= i.

And they are simple poles?

No answer in the book

Thanks for your help.

2. ## Re: Quick Residue theorem question

Originally Posted by olski1
I just have a quick question on a problem in the text book,

Determine the singular points of:

1/(z^3+i)

Am i right in assuming there are only 2 singular point, z=(-i)^1/3 and z= i.

And they are simple poles?

No answer in the book

Thanks for your help.
Well, I think you should know that there are three $3$-roots of unity. And then, $z^3=i\Leftrightarrow (iz)^3=1$ should tell you how many solutions there are.