Help..
How can i apply integral test to this \[\frac{ 1 }{ k( Logk)^{p}}\]
what are the limits ? 2 to infinity ?
yes..
\(\large \sum \limits_2^{\infty } \frac{1}{k (\ln k)^p} \) converges \(\iff\) \(\large \int \limits_2^{\infty} \frac{1}{k(\ln k )^p}dk \) is finite
\(\large \sum \limits_2^{\infty } \frac{1}{k (\ln k)^p} \) diverges \(\iff\) \(\large \int \limits_2^{\infty} \frac{1}{k(\ln k )^p}dk \) is not finite
For which p the integral is finite ?
evaluate the right side integral and see when it is finite
p is greater than 1 ?
ln k = u 1/k dk = du \(\large \int \limits_{\#}^{*} 1/t^p dt\) analyze this
\(\large \frac{t^{-p+1}}{-p+1} \Big|_{\ln 2}^{\infty } \)
when p < 1, clearly it diverges
p =1 also it diverges p > 1 is when it wud be finite,
let me know if u want discuss the reasoning behind these 3 conclusions
why at p=1 diverges? because its result becomes 0/0 then the integral is undefined ?
nope
\(\large \int \limits_{\ln 2}^{\infty} 1/t dt = \ln t \Big|_{\ln 2}^{\infty} = \ln \infty - **** = \infty \)
so, p = 1 also diverges
thank you..
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