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i need to tell if the following sequence converges or diverges
[tex]\sum[/tex](-1)n-1lnp(n)/n {p>0}
(n from 1 to infinity)
what i think i need to do is take the positive version of this series
[tex]\sum[/tex]lnp(n)/n {p>0}
(n from 1 to infinity)
if the positive series converges than the original must also, if not i can use leibnitz to tell me its behaviour
the problem it the "p", surely {p>0} is not enough information, do i not need to know if p>1 or p<1?
i can integrate [tex]\int[/tex](lnp(x)/x)dx ===> t=lnx dt=dx/x
[tex]\int[/tex]tpdt
=tp+1/(p+1) =...
...lnp+1(n)|[tex]^{infinity}_{1}[/tex]
if P>-1 [tex]\sum[/tex]lnp(n)/n diverges
if P<-1 [tex]\sum[/tex]lnp(n)/n converges
if p=-1 [tex]\sum[/tex]lnp(n)/n diverges
but i am told that {p>0} therefor i am only left with one option
if P>-1 [tex]\sum[/tex]lnp(n)/n diverges
so now i need to check if:
- lim An = 0
- An+1< An
[tex]\sum[/tex](-1)n-1lnp(n)/n {p>0}
(n from 1 to infinity)
what i think i need to do is take the positive version of this series
[tex]\sum[/tex]lnp(n)/n {p>0}
(n from 1 to infinity)
if the positive series converges than the original must also, if not i can use leibnitz to tell me its behaviour
the problem it the "p", surely {p>0} is not enough information, do i not need to know if p>1 or p<1?
i can integrate [tex]\int[/tex](lnp(x)/x)dx ===> t=lnx dt=dx/x
[tex]\int[/tex]tpdt
=tp+1/(p+1) =...
...lnp+1(n)|[tex]^{infinity}_{1}[/tex]
if P>-1 [tex]\sum[/tex]lnp(n)/n diverges
if P<-1 [tex]\sum[/tex]lnp(n)/n converges
if p=-1 [tex]\sum[/tex]lnp(n)/n diverges
but i am told that {p>0} therefor i am only left with one option
if P>-1 [tex]\sum[/tex]lnp(n)/n diverges
so now i need to check if:
- lim An = 0
- An+1< An
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