Limit of a sequence where $U_n = frac{(log n )^p}{n}$












0














What is the limit of this sequence where , $U_n = frac{(log n )^p}{n}$ where $p ge 0$.



I have done this problem when $p$ is an integer.
Sorry but I am not too much familiar with writing questions in stack exchange.










share|cite|improve this question
























  • See if you can exploit propositions 2.1 and 2.2 from here
    – rtybase
    Nov 25 '18 at 10:07






  • 1




    If you know the results for $p in mathbb N$, note that for general $p$, there is a $kin mathbb N$ s.t. $k leqslant p<k+1$, and to get the limit, try the squeezing theorem.
    – xbh
    Nov 25 '18 at 13:19
















0














What is the limit of this sequence where , $U_n = frac{(log n )^p}{n}$ where $p ge 0$.



I have done this problem when $p$ is an integer.
Sorry but I am not too much familiar with writing questions in stack exchange.










share|cite|improve this question
























  • See if you can exploit propositions 2.1 and 2.2 from here
    – rtybase
    Nov 25 '18 at 10:07






  • 1




    If you know the results for $p in mathbb N$, note that for general $p$, there is a $kin mathbb N$ s.t. $k leqslant p<k+1$, and to get the limit, try the squeezing theorem.
    – xbh
    Nov 25 '18 at 13:19














0












0








0







What is the limit of this sequence where , $U_n = frac{(log n )^p}{n}$ where $p ge 0$.



I have done this problem when $p$ is an integer.
Sorry but I am not too much familiar with writing questions in stack exchange.










share|cite|improve this question















What is the limit of this sequence where , $U_n = frac{(log n )^p}{n}$ where $p ge 0$.



I have done this problem when $p$ is an integer.
Sorry but I am not too much familiar with writing questions in stack exchange.







sequences-and-series limits






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Nov 25 '18 at 9:55







user616975

















asked Nov 25 '18 at 9:46









Supriyo Banerjee

595




595












  • See if you can exploit propositions 2.1 and 2.2 from here
    – rtybase
    Nov 25 '18 at 10:07






  • 1




    If you know the results for $p in mathbb N$, note that for general $p$, there is a $kin mathbb N$ s.t. $k leqslant p<k+1$, and to get the limit, try the squeezing theorem.
    – xbh
    Nov 25 '18 at 13:19


















  • See if you can exploit propositions 2.1 and 2.2 from here
    – rtybase
    Nov 25 '18 at 10:07






  • 1




    If you know the results for $p in mathbb N$, note that for general $p$, there is a $kin mathbb N$ s.t. $k leqslant p<k+1$, and to get the limit, try the squeezing theorem.
    – xbh
    Nov 25 '18 at 13:19
















See if you can exploit propositions 2.1 and 2.2 from here
– rtybase
Nov 25 '18 at 10:07




See if you can exploit propositions 2.1 and 2.2 from here
– rtybase
Nov 25 '18 at 10:07




1




1




If you know the results for $p in mathbb N$, note that for general $p$, there is a $kin mathbb N$ s.t. $k leqslant p<k+1$, and to get the limit, try the squeezing theorem.
– xbh
Nov 25 '18 at 13:19




If you know the results for $p in mathbb N$, note that for general $p$, there is a $kin mathbb N$ s.t. $k leqslant p<k+1$, and to get the limit, try the squeezing theorem.
– xbh
Nov 25 '18 at 13:19










1 Answer
1






active

oldest

votes


















0














We have that



$$frac{(log n )^p}{n}=e^{plog(log n)-log n} to 0$$



indeed



$$plog(log n)-log n=log nleft(pfrac{log(log n)}{log n}-1right)to -infty$$



since



$$frac{log(log n)}{log n} to 0$$



which can be easily proved by $frac{log x}x to 0$ as $x to infty$ by $x=log y$ and $y to infty$.






share|cite|improve this answer





















  • Why the downvote, something wrong?
    – gimusi
    Nov 25 '18 at 18:53










  • Can we write $lim$ $x tends to infinity$ $f(n)g(n)$ = $lim$ $x tends to infinity$ $f(n)$ × $lim$ $x tends to infinity$ $g(n)$. When one of the sequence diverges? I don't know...
    – Supriyo Banerjee
    Nov 26 '18 at 3:08






  • 1




    Note that here we are using something different that is $$lim_{nto infty} f(n)=lim_{nto infty} g(n)cdot h(n)$$ and using the fact that $g(n)to infty$ and $h(n)to -1$ and that’s leads to a not indeterminate form.
    – gimusi
    Nov 26 '18 at 6:28











Your Answer





StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3012636%2flimit-of-a-sequence-where-u-n-frac-log-n-pn%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes









0














We have that



$$frac{(log n )^p}{n}=e^{plog(log n)-log n} to 0$$



indeed



$$plog(log n)-log n=log nleft(pfrac{log(log n)}{log n}-1right)to -infty$$



since



$$frac{log(log n)}{log n} to 0$$



which can be easily proved by $frac{log x}x to 0$ as $x to infty$ by $x=log y$ and $y to infty$.






share|cite|improve this answer





















  • Why the downvote, something wrong?
    – gimusi
    Nov 25 '18 at 18:53










  • Can we write $lim$ $x tends to infinity$ $f(n)g(n)$ = $lim$ $x tends to infinity$ $f(n)$ × $lim$ $x tends to infinity$ $g(n)$. When one of the sequence diverges? I don't know...
    – Supriyo Banerjee
    Nov 26 '18 at 3:08






  • 1




    Note that here we are using something different that is $$lim_{nto infty} f(n)=lim_{nto infty} g(n)cdot h(n)$$ and using the fact that $g(n)to infty$ and $h(n)to -1$ and that’s leads to a not indeterminate form.
    – gimusi
    Nov 26 '18 at 6:28
















0














We have that



$$frac{(log n )^p}{n}=e^{plog(log n)-log n} to 0$$



indeed



$$plog(log n)-log n=log nleft(pfrac{log(log n)}{log n}-1right)to -infty$$



since



$$frac{log(log n)}{log n} to 0$$



which can be easily proved by $frac{log x}x to 0$ as $x to infty$ by $x=log y$ and $y to infty$.






share|cite|improve this answer





















  • Why the downvote, something wrong?
    – gimusi
    Nov 25 '18 at 18:53










  • Can we write $lim$ $x tends to infinity$ $f(n)g(n)$ = $lim$ $x tends to infinity$ $f(n)$ × $lim$ $x tends to infinity$ $g(n)$. When one of the sequence diverges? I don't know...
    – Supriyo Banerjee
    Nov 26 '18 at 3:08






  • 1




    Note that here we are using something different that is $$lim_{nto infty} f(n)=lim_{nto infty} g(n)cdot h(n)$$ and using the fact that $g(n)to infty$ and $h(n)to -1$ and that’s leads to a not indeterminate form.
    – gimusi
    Nov 26 '18 at 6:28














0












0








0






We have that



$$frac{(log n )^p}{n}=e^{plog(log n)-log n} to 0$$



indeed



$$plog(log n)-log n=log nleft(pfrac{log(log n)}{log n}-1right)to -infty$$



since



$$frac{log(log n)}{log n} to 0$$



which can be easily proved by $frac{log x}x to 0$ as $x to infty$ by $x=log y$ and $y to infty$.






share|cite|improve this answer












We have that



$$frac{(log n )^p}{n}=e^{plog(log n)-log n} to 0$$



indeed



$$plog(log n)-log n=log nleft(pfrac{log(log n)}{log n}-1right)to -infty$$



since



$$frac{log(log n)}{log n} to 0$$



which can be easily proved by $frac{log x}x to 0$ as $x to infty$ by $x=log y$ and $y to infty$.







share|cite|improve this answer












share|cite|improve this answer



share|cite|improve this answer










answered Nov 25 '18 at 18:32









gimusi

1




1












  • Why the downvote, something wrong?
    – gimusi
    Nov 25 '18 at 18:53










  • Can we write $lim$ $x tends to infinity$ $f(n)g(n)$ = $lim$ $x tends to infinity$ $f(n)$ × $lim$ $x tends to infinity$ $g(n)$. When one of the sequence diverges? I don't know...
    – Supriyo Banerjee
    Nov 26 '18 at 3:08






  • 1




    Note that here we are using something different that is $$lim_{nto infty} f(n)=lim_{nto infty} g(n)cdot h(n)$$ and using the fact that $g(n)to infty$ and $h(n)to -1$ and that’s leads to a not indeterminate form.
    – gimusi
    Nov 26 '18 at 6:28


















  • Why the downvote, something wrong?
    – gimusi
    Nov 25 '18 at 18:53










  • Can we write $lim$ $x tends to infinity$ $f(n)g(n)$ = $lim$ $x tends to infinity$ $f(n)$ × $lim$ $x tends to infinity$ $g(n)$. When one of the sequence diverges? I don't know...
    – Supriyo Banerjee
    Nov 26 '18 at 3:08






  • 1




    Note that here we are using something different that is $$lim_{nto infty} f(n)=lim_{nto infty} g(n)cdot h(n)$$ and using the fact that $g(n)to infty$ and $h(n)to -1$ and that’s leads to a not indeterminate form.
    – gimusi
    Nov 26 '18 at 6:28
















Why the downvote, something wrong?
– gimusi
Nov 25 '18 at 18:53




Why the downvote, something wrong?
– gimusi
Nov 25 '18 at 18:53












Can we write $lim$ $x tends to infinity$ $f(n)g(n)$ = $lim$ $x tends to infinity$ $f(n)$ × $lim$ $x tends to infinity$ $g(n)$. When one of the sequence diverges? I don't know...
– Supriyo Banerjee
Nov 26 '18 at 3:08




Can we write $lim$ $x tends to infinity$ $f(n)g(n)$ = $lim$ $x tends to infinity$ $f(n)$ × $lim$ $x tends to infinity$ $g(n)$. When one of the sequence diverges? I don't know...
– Supriyo Banerjee
Nov 26 '18 at 3:08




1




1




Note that here we are using something different that is $$lim_{nto infty} f(n)=lim_{nto infty} g(n)cdot h(n)$$ and using the fact that $g(n)to infty$ and $h(n)to -1$ and that’s leads to a not indeterminate form.
– gimusi
Nov 26 '18 at 6:28




Note that here we are using something different that is $$lim_{nto infty} f(n)=lim_{nto infty} g(n)cdot h(n)$$ and using the fact that $g(n)to infty$ and $h(n)to -1$ and that’s leads to a not indeterminate form.
– gimusi
Nov 26 '18 at 6:28


















draft saved

draft discarded




















































Thanks for contributing an answer to Mathematics Stack Exchange!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


Use MathJax to format equations. MathJax reference.


To learn more, see our tips on writing great answers.





Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


Please pay close attention to the following guidance:


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3012636%2flimit-of-a-sequence-where-u-n-frac-log-n-pn%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

Plaza Victoria

Puebla de Zaragoza

Musa