- #1
sid9221
- 111
- 0
Now for the proof of convergence/divergence of the geometric series we first deduce the Nth partial sum which is given by:
[tex] \frac{r(1-r^n)}{1-r} [/tex]
Now for 0<r<1 this become [tex] \frac{1}{1-r} [/tex] which clearly converges by AOL
At r>1 it's similarly obvious why it diverges.
But at r=1, I'm a bit confused. The text say's that it diverges but when I try to work it out I get:
[tex] 1^n -> 1 [/tex]
[tex] S_n = \frac{C*0}{1-1} [/tex]
which measn S_n = 0 which is confusing as it seems to indicate convergence ?
Am I suppose to interpret 0/0 as implying divergence ?
[tex] \frac{r(1-r^n)}{1-r} [/tex]
Now for 0<r<1 this become [tex] \frac{1}{1-r} [/tex] which clearly converges by AOL
At r>1 it's similarly obvious why it diverges.
But at r=1, I'm a bit confused. The text say's that it diverges but when I try to work it out I get:
[tex] 1^n -> 1 [/tex]
[tex] S_n = \frac{C*0}{1-1} [/tex]
which measn S_n = 0 which is confusing as it seems to indicate convergence ?
Am I suppose to interpret 0/0 as implying divergence ?