Integral involving the logarithm












0














Let $p$ and $q$ be two positive integers, I wonder if the following integral admits a closed-form and if yeah so in which way it should be worked out.



$$int_{0}^{1}frac{ln(1-x^p)ln(1+x^q)}{x^{p+q}}dx,=sum_{n,kgeq1}frac{(-1)^n}{nk(np+kq+1-p-q)}$$










share|cite|improve this question
























  • What have you tried by yourself?
    – mrtaurho
    2 days ago










  • using Tylor series of $ln(1-x^q)$ and $ln(1+x^p)$
    – Kays Tomy
    2 days ago










  • What have you found so far from your attempts?
    – clathratus
    2 days ago










  • Alternating series as it is shown above
    – Kays Tomy
    2 days ago
















0














Let $p$ and $q$ be two positive integers, I wonder if the following integral admits a closed-form and if yeah so in which way it should be worked out.



$$int_{0}^{1}frac{ln(1-x^p)ln(1+x^q)}{x^{p+q}}dx,=sum_{n,kgeq1}frac{(-1)^n}{nk(np+kq+1-p-q)}$$










share|cite|improve this question
























  • What have you tried by yourself?
    – mrtaurho
    2 days ago










  • using Tylor series of $ln(1-x^q)$ and $ln(1+x^p)$
    – Kays Tomy
    2 days ago










  • What have you found so far from your attempts?
    – clathratus
    2 days ago










  • Alternating series as it is shown above
    – Kays Tomy
    2 days ago














0












0








0


3





Let $p$ and $q$ be two positive integers, I wonder if the following integral admits a closed-form and if yeah so in which way it should be worked out.



$$int_{0}^{1}frac{ln(1-x^p)ln(1+x^q)}{x^{p+q}}dx,=sum_{n,kgeq1}frac{(-1)^n}{nk(np+kq+1-p-q)}$$










share|cite|improve this question















Let $p$ and $q$ be two positive integers, I wonder if the following integral admits a closed-form and if yeah so in which way it should be worked out.



$$int_{0}^{1}frac{ln(1-x^p)ln(1+x^q)}{x^{p+q}}dx,=sum_{n,kgeq1}frac{(-1)^n}{nk(np+kq+1-p-q)}$$







integration definite-integrals power-series






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited 2 days ago









Masacroso

12.9k41746




12.9k41746










asked 2 days ago









Kays Tomy

1977




1977












  • What have you tried by yourself?
    – mrtaurho
    2 days ago










  • using Tylor series of $ln(1-x^q)$ and $ln(1+x^p)$
    – Kays Tomy
    2 days ago










  • What have you found so far from your attempts?
    – clathratus
    2 days ago










  • Alternating series as it is shown above
    – Kays Tomy
    2 days ago


















  • What have you tried by yourself?
    – mrtaurho
    2 days ago










  • using Tylor series of $ln(1-x^q)$ and $ln(1+x^p)$
    – Kays Tomy
    2 days ago










  • What have you found so far from your attempts?
    – clathratus
    2 days ago










  • Alternating series as it is shown above
    – Kays Tomy
    2 days ago
















What have you tried by yourself?
– mrtaurho
2 days ago




What have you tried by yourself?
– mrtaurho
2 days ago












using Tylor series of $ln(1-x^q)$ and $ln(1+x^p)$
– Kays Tomy
2 days ago




using Tylor series of $ln(1-x^q)$ and $ln(1+x^p)$
– Kays Tomy
2 days ago












What have you found so far from your attempts?
– clathratus
2 days ago




What have you found so far from your attempts?
– clathratus
2 days ago












Alternating series as it is shown above
– Kays Tomy
2 days ago




Alternating series as it is shown above
– Kays Tomy
2 days ago










1 Answer
1






active

oldest

votes


















0














Here is a partial answer in terms of an infinite series. After expanding both logarithms into their respective Maclaurin series, integrating term by term and applying a certain series representation of the digamma function, I've obtained this series:
$$int_0^1 frac{log(1-x^p)log(1+x^q)}{x^{p+q}},dx=sum_{kge 0} (-1)^{k+1} frac{psi^{(0)}left(frac{kq+1}{p}right)+gamma}{(k+1)(kq-p+1)}$$
Where $psi^{(0)}$ $(=Gamma'/Gamma )$ is the digamma function and $gamma$ ($=lim_{ntoinfty} H_n-log n$) is the Euler-Mascheroni constant. I'm not sure how to simplify this sum, which appears especially challenging because of the appearance of digamma function.



Checking the basic case $q=0$ yields
$$int_0^1 frac{log(1-x^p)}{x^p},dx=frac{psi^{(0)}(1/p)+gamma}{p-1}$$
Which seems to agree with some of the computational verifications I've done.






share|cite|improve this answer





















    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%2f3052358%2fintegral-involving-the-logarithm%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














    Here is a partial answer in terms of an infinite series. After expanding both logarithms into their respective Maclaurin series, integrating term by term and applying a certain series representation of the digamma function, I've obtained this series:
    $$int_0^1 frac{log(1-x^p)log(1+x^q)}{x^{p+q}},dx=sum_{kge 0} (-1)^{k+1} frac{psi^{(0)}left(frac{kq+1}{p}right)+gamma}{(k+1)(kq-p+1)}$$
    Where $psi^{(0)}$ $(=Gamma'/Gamma )$ is the digamma function and $gamma$ ($=lim_{ntoinfty} H_n-log n$) is the Euler-Mascheroni constant. I'm not sure how to simplify this sum, which appears especially challenging because of the appearance of digamma function.



    Checking the basic case $q=0$ yields
    $$int_0^1 frac{log(1-x^p)}{x^p},dx=frac{psi^{(0)}(1/p)+gamma}{p-1}$$
    Which seems to agree with some of the computational verifications I've done.






    share|cite|improve this answer


























      0














      Here is a partial answer in terms of an infinite series. After expanding both logarithms into their respective Maclaurin series, integrating term by term and applying a certain series representation of the digamma function, I've obtained this series:
      $$int_0^1 frac{log(1-x^p)log(1+x^q)}{x^{p+q}},dx=sum_{kge 0} (-1)^{k+1} frac{psi^{(0)}left(frac{kq+1}{p}right)+gamma}{(k+1)(kq-p+1)}$$
      Where $psi^{(0)}$ $(=Gamma'/Gamma )$ is the digamma function and $gamma$ ($=lim_{ntoinfty} H_n-log n$) is the Euler-Mascheroni constant. I'm not sure how to simplify this sum, which appears especially challenging because of the appearance of digamma function.



      Checking the basic case $q=0$ yields
      $$int_0^1 frac{log(1-x^p)}{x^p},dx=frac{psi^{(0)}(1/p)+gamma}{p-1}$$
      Which seems to agree with some of the computational verifications I've done.






      share|cite|improve this answer
























        0












        0








        0






        Here is a partial answer in terms of an infinite series. After expanding both logarithms into their respective Maclaurin series, integrating term by term and applying a certain series representation of the digamma function, I've obtained this series:
        $$int_0^1 frac{log(1-x^p)log(1+x^q)}{x^{p+q}},dx=sum_{kge 0} (-1)^{k+1} frac{psi^{(0)}left(frac{kq+1}{p}right)+gamma}{(k+1)(kq-p+1)}$$
        Where $psi^{(0)}$ $(=Gamma'/Gamma )$ is the digamma function and $gamma$ ($=lim_{ntoinfty} H_n-log n$) is the Euler-Mascheroni constant. I'm not sure how to simplify this sum, which appears especially challenging because of the appearance of digamma function.



        Checking the basic case $q=0$ yields
        $$int_0^1 frac{log(1-x^p)}{x^p},dx=frac{psi^{(0)}(1/p)+gamma}{p-1}$$
        Which seems to agree with some of the computational verifications I've done.






        share|cite|improve this answer












        Here is a partial answer in terms of an infinite series. After expanding both logarithms into their respective Maclaurin series, integrating term by term and applying a certain series representation of the digamma function, I've obtained this series:
        $$int_0^1 frac{log(1-x^p)log(1+x^q)}{x^{p+q}},dx=sum_{kge 0} (-1)^{k+1} frac{psi^{(0)}left(frac{kq+1}{p}right)+gamma}{(k+1)(kq-p+1)}$$
        Where $psi^{(0)}$ $(=Gamma'/Gamma )$ is the digamma function and $gamma$ ($=lim_{ntoinfty} H_n-log n$) is the Euler-Mascheroni constant. I'm not sure how to simplify this sum, which appears especially challenging because of the appearance of digamma function.



        Checking the basic case $q=0$ yields
        $$int_0^1 frac{log(1-x^p)}{x^p},dx=frac{psi^{(0)}(1/p)+gamma}{p-1}$$
        Which seems to agree with some of the computational verifications I've done.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered 2 days ago









        Zachary

        2,2891211




        2,2891211






























            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%2f3052358%2fintegral-involving-the-logarithm%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

            Human spaceflight

            Can not write log (Is /dev/pts mounted?) - openpty in Ubuntu-on-Windows?

            張江高科駅