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What is this?

I have no math training beyond high school 45 years ago, and I don’t remember much of it. However I am doing a project, and I find the series below is quite valuable. But I do not know what it is or what it is called. It is like this:

X + 1 (1/x + 1/x^2 + 1/x^3 . . . ).

It comes ever closer to a value which is very significant in what I am doing. I wonder if someone can tell me what this is called, and what it can be used for.
 

Answers and Replies

rock.freak667
Homework Helper
6,230
31
Well what is in the brackets is a geometric progrssion
 
Avodyne
Science Advisor
1,396
85
Yes, the part in parentheses is a geometric series that can be summed (provided the absolute value of x is bigger than 1):

1/x + 1/x^2 + 1/x^3 + ... = 1/(x-1)
 
Thank you!
 
rock.freak667
Homework Helper
6,230
31
Yes, the part in parentheses is a geometric series that can be summed (provided the absolute value of x is bigger than 1):

1/x + 1/x^2 + 1/x^3 + ... = 1/(x-1)
For that sum to converge,

|1/x|<1
 

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