Is it possible for radius of convergence to be negative?

1. Dec 1, 2006

jkh4

is it possible for "R" (radius of convergence) to be negative?

is it possible for "R" (radius of convergence) to be negative?

for example: -|x|<1 and R=-1?

Last edited: Dec 1, 2006
2. Dec 1, 2006

Hurkyl

Staff Emeritus
What does the definition say?

3. Dec 1, 2006

Office_Shredder

Staff Emeritus
If -|x|< 1,then x can be any number. So it's not a very useful thing to say

4. Dec 1, 2006

HallsofIvy

Staff Emeritus
As Hurkyl said, take any Calculus book and look up the definition of "radius of convergence"!