Dell
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find the possible values of p so that the following converges
infinity
\sum1/(ln(n)*np)
n=2
what i thought of doing was integrating to find the values of p such that the integral will give me an answer not infinity.
\intdx/(ln(x)*xp) from 2-infnity
i thought of using substitution as
t=ln(x)
x=et
dt=dx/x
\intdt/(t*et(p-1)) from ln2-infinty
but i have no idea how to continue from here, i think that if p<=1 then my integral will diverge since lim(t->inf) will not be 0, but i am not sure, i know that with a series if lim(n->inf) is not 0 then the series diverges, is this true for integrals as well,
even so, if i know that p<=1 diverges, this does not automatically mean that anything else converges, since lim(n->inf)An=0 doesn't mean necessarily converges, how do i find the values for p where i KNOW the integral diverges??
infinity
\sum1/(ln(n)*np)
n=2
what i thought of doing was integrating to find the values of p such that the integral will give me an answer not infinity.
\intdx/(ln(x)*xp) from 2-infnity
i thought of using substitution as
t=ln(x)
x=et
dt=dx/x
\intdt/(t*et(p-1)) from ln2-infinty
but i have no idea how to continue from here, i think that if p<=1 then my integral will diverge since lim(t->inf) will not be 0, but i am not sure, i know that with a series if lim(n->inf) is not 0 then the series diverges, is this true for integrals as well,
even so, if i know that p<=1 diverges, this does not automatically mean that anything else converges, since lim(n->inf)An=0 doesn't mean necessarily converges, how do i find the values for p where i KNOW the integral diverges??