- #1
GreenPrint
- 1,196
- 0
Determine weather or not the following series converges or diverges.
sum[k=1,inf] 2/(k^2-1)
I applied the limit comparison test with 1/k^2
2* lim k->inf [ 1/(k^2-1) ] /(1/k^2) = 2*lim k->inf k^2/(k^2-1) =H 2
then because
sum[k=1,inf] 1/k^2 is a convergent p-series then sum[k=1,inf] 2/(k^2-1) must also converge by the limit comparison test.
I plugged this into wolfram alpha and it said that the sum does not converge. Am I doing something wrong? Thanks for any help.
This is what I put into wolfram alpha
sum[n=1,inf] of 2/(k^2-1)
sum[k=1,inf] 2/(k^2-1)
I applied the limit comparison test with 1/k^2
2* lim k->inf [ 1/(k^2-1) ] /(1/k^2) = 2*lim k->inf k^2/(k^2-1) =H 2
then because
sum[k=1,inf] 1/k^2 is a convergent p-series then sum[k=1,inf] 2/(k^2-1) must also converge by the limit comparison test.
I plugged this into wolfram alpha and it said that the sum does not converge. Am I doing something wrong? Thanks for any help.
This is what I put into wolfram alpha
sum[n=1,inf] of 2/(k^2-1)