why is the limit of this expression equal to 1? The 2019 Stack Overflow Developer Survey Results Are In Announcing the arrival of Valued Associate #679: Cesar Manara Planned maintenance scheduled April 17/18, 2019 at 00:00UTC (8:00pm US/Eastern)Finding the limit of the following expressionReforming series expression for limit of e$lim_x rightarrow inftyleft(fracpi2-tan^-1xright)^Largefrac1x$ Why aren't these two limits equal when they should be?What is the value of this limit?limit of an expressionUsing a definite integral find the value of $lim_nrightarrow infty (frac1n+frac1n+1+…+frac12n)$Why is the following limit operation valid?Is this expression on limit valid and/or meaningful?Why does this limit equal 0?A Problem on the Limit of an Integral

Multi tool use
Multi tool use

Sub-subscripts in strings cause different spacings than subscripts

Variable with quotation marks "$()"

My body leaves; my core can stay

What information about me do stores get via my credit card?

Separating matrix elements by lines

Working through the single responsibility principle (SRP) in Python when calls are expensive

Does Parliament need to approve the new Brexit delay to 31 October 2019?

Did the new image of black hole confirm the general theory of relativity?

Identify 80s or 90s comics with ripped creatures (not dwarves)

Can each chord in a progression create its own key?

Deal with toxic manager when you can't quit

ELI5: Why do they say that Israel would have been the fourth country to land a spacecraft on the Moon and why do they call it low cost?

Why are PDP-7-style microprogrammed instructions out of vogue?

What aspect of planet Earth must be changed to prevent the industrial revolution?

Make it rain characters

How did the audience guess the pentatonic scale in Bobby McFerrin's presentation?

Example of compact Riemannian manifold with only one geodesic.

What do I do when my TA workload is more than expected?

Am I ethically obligated to go into work on an off day if the reason is sudden?

Keeping a retro style to sci-fi spaceships?

Why doesn't a hydraulic lever violate conservation of energy?

how can a perfect fourth interval be considered either consonant or dissonant?

How to type a long/em dash `—`

Can a flute soloist sit?



why is the limit of this expression equal to 1?



The 2019 Stack Overflow Developer Survey Results Are In
Announcing the arrival of Valued Associate #679: Cesar Manara
Planned maintenance scheduled April 17/18, 2019 at 00:00UTC (8:00pm US/Eastern)Finding the limit of the following expressionReforming series expression for limit of e$lim_x rightarrow inftyleft(fracpi2-tan^-1xright)^Largefrac1x$ Why aren't these two limits equal when they should be?What is the value of this limit?limit of an expressionUsing a definite integral find the value of $lim_nrightarrow infty (frac1n+frac1n+1+…+frac12n)$Why is the following limit operation valid?Is this expression on limit valid and/or meaningful?Why does this limit equal 0?A Problem on the Limit of an Integral










1












$begingroup$


I found something which I find confusing.



$$
lim_nrightarrow infty fracn!n^k(n-k)! =1
$$



It was something I encountered while learning probability on this webpage.










share|cite|improve this question











$endgroup$
















    1












    $begingroup$


    I found something which I find confusing.



    $$
    lim_nrightarrow infty fracn!n^k(n-k)! =1
    $$



    It was something I encountered while learning probability on this webpage.










    share|cite|improve this question











    $endgroup$














      1












      1








      1


      2



      $begingroup$


      I found something which I find confusing.



      $$
      lim_nrightarrow infty fracn!n^k(n-k)! =1
      $$



      It was something I encountered while learning probability on this webpage.










      share|cite|improve this question











      $endgroup$




      I found something which I find confusing.



      $$
      lim_nrightarrow infty fracn!n^k(n-k)! =1
      $$



      It was something I encountered while learning probability on this webpage.







      limits






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited 2 hours ago







      billyandr

















      asked 2 hours ago









      billyandrbillyandr

      155




      155




















          2 Answers
          2






          active

          oldest

          votes


















          5












          $begingroup$

          It is rather obvious if you cancel the factorials:



          $$fracn!n^k(n-k)! =fracoverbracen(n-1)cdots (n-k+1)^k; factorsn^k= 1cdot left(1-frac1nright)cdots left(1-frack-1nright)stackreln to inftylongrightarrow 1$$






          share|cite|improve this answer









          $endgroup$












          • $begingroup$
            Thank you so much. I didn't know it was right there under my eyes.
            $endgroup$
            – billyandr
            1 hour ago










          • $begingroup$
            You are welcome. This "not seeing the obvious" just happens once in a while, I think, to all who do maths. So, it is good to have a math platform like this one. :-)
            $endgroup$
            – trancelocation
            1 hour ago



















          2












          $begingroup$

          $$a_n=fracn!n^k(n-k)! implies log(a_n)=log(n!)-k log(n)-log((n-k)!)$$



          Use Stirling approximation and continue with Taylor series to get
          $$log(a_n)=frack(1-k)2 n+Oleft(frac1n^2right)$$ Continue with Taylor
          $$a_n=e^log(a_n)=1+frack(1-k)2 n+Oleft(frac1n^2right)$$






          share|cite|improve this answer









          $endgroup$












          • $begingroup$
            This has already a slight touch of overkill, hasn't it? :-)
            $endgroup$
            – trancelocation
            1 hour ago










          • $begingroup$
            @trancelocation. You are totally right for the limit. One of my manias is to always look at the approach to the limit. Have a look at matheducators.stackexchange.com/questions/8339/… . Cheers :-)
            $endgroup$
            – Claude Leibovici
            1 hour ago












          Your Answer








          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%2f3185830%2fwhy-is-the-limit-of-this-expression-equal-to-1%23new-answer', 'question_page');

          );

          Post as a guest















          Required, but never shown

























          2 Answers
          2






          active

          oldest

          votes








          2 Answers
          2






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes









          5












          $begingroup$

          It is rather obvious if you cancel the factorials:



          $$fracn!n^k(n-k)! =fracoverbracen(n-1)cdots (n-k+1)^k; factorsn^k= 1cdot left(1-frac1nright)cdots left(1-frack-1nright)stackreln to inftylongrightarrow 1$$






          share|cite|improve this answer









          $endgroup$












          • $begingroup$
            Thank you so much. I didn't know it was right there under my eyes.
            $endgroup$
            – billyandr
            1 hour ago










          • $begingroup$
            You are welcome. This "not seeing the obvious" just happens once in a while, I think, to all who do maths. So, it is good to have a math platform like this one. :-)
            $endgroup$
            – trancelocation
            1 hour ago
















          5












          $begingroup$

          It is rather obvious if you cancel the factorials:



          $$fracn!n^k(n-k)! =fracoverbracen(n-1)cdots (n-k+1)^k; factorsn^k= 1cdot left(1-frac1nright)cdots left(1-frack-1nright)stackreln to inftylongrightarrow 1$$






          share|cite|improve this answer









          $endgroup$












          • $begingroup$
            Thank you so much. I didn't know it was right there under my eyes.
            $endgroup$
            – billyandr
            1 hour ago










          • $begingroup$
            You are welcome. This "not seeing the obvious" just happens once in a while, I think, to all who do maths. So, it is good to have a math platform like this one. :-)
            $endgroup$
            – trancelocation
            1 hour ago














          5












          5








          5





          $begingroup$

          It is rather obvious if you cancel the factorials:



          $$fracn!n^k(n-k)! =fracoverbracen(n-1)cdots (n-k+1)^k; factorsn^k= 1cdot left(1-frac1nright)cdots left(1-frack-1nright)stackreln to inftylongrightarrow 1$$






          share|cite|improve this answer









          $endgroup$



          It is rather obvious if you cancel the factorials:



          $$fracn!n^k(n-k)! =fracoverbracen(n-1)cdots (n-k+1)^k; factorsn^k= 1cdot left(1-frac1nright)cdots left(1-frack-1nright)stackreln to inftylongrightarrow 1$$







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered 1 hour ago









          trancelocationtrancelocation

          14.1k1829




          14.1k1829











          • $begingroup$
            Thank you so much. I didn't know it was right there under my eyes.
            $endgroup$
            – billyandr
            1 hour ago










          • $begingroup$
            You are welcome. This "not seeing the obvious" just happens once in a while, I think, to all who do maths. So, it is good to have a math platform like this one. :-)
            $endgroup$
            – trancelocation
            1 hour ago

















          • $begingroup$
            Thank you so much. I didn't know it was right there under my eyes.
            $endgroup$
            – billyandr
            1 hour ago










          • $begingroup$
            You are welcome. This "not seeing the obvious" just happens once in a while, I think, to all who do maths. So, it is good to have a math platform like this one. :-)
            $endgroup$
            – trancelocation
            1 hour ago
















          $begingroup$
          Thank you so much. I didn't know it was right there under my eyes.
          $endgroup$
          – billyandr
          1 hour ago




          $begingroup$
          Thank you so much. I didn't know it was right there under my eyes.
          $endgroup$
          – billyandr
          1 hour ago












          $begingroup$
          You are welcome. This "not seeing the obvious" just happens once in a while, I think, to all who do maths. So, it is good to have a math platform like this one. :-)
          $endgroup$
          – trancelocation
          1 hour ago





          $begingroup$
          You are welcome. This "not seeing the obvious" just happens once in a while, I think, to all who do maths. So, it is good to have a math platform like this one. :-)
          $endgroup$
          – trancelocation
          1 hour ago












          2












          $begingroup$

          $$a_n=fracn!n^k(n-k)! implies log(a_n)=log(n!)-k log(n)-log((n-k)!)$$



          Use Stirling approximation and continue with Taylor series to get
          $$log(a_n)=frack(1-k)2 n+Oleft(frac1n^2right)$$ Continue with Taylor
          $$a_n=e^log(a_n)=1+frack(1-k)2 n+Oleft(frac1n^2right)$$






          share|cite|improve this answer









          $endgroup$












          • $begingroup$
            This has already a slight touch of overkill, hasn't it? :-)
            $endgroup$
            – trancelocation
            1 hour ago










          • $begingroup$
            @trancelocation. You are totally right for the limit. One of my manias is to always look at the approach to the limit. Have a look at matheducators.stackexchange.com/questions/8339/… . Cheers :-)
            $endgroup$
            – Claude Leibovici
            1 hour ago
















          2












          $begingroup$

          $$a_n=fracn!n^k(n-k)! implies log(a_n)=log(n!)-k log(n)-log((n-k)!)$$



          Use Stirling approximation and continue with Taylor series to get
          $$log(a_n)=frack(1-k)2 n+Oleft(frac1n^2right)$$ Continue with Taylor
          $$a_n=e^log(a_n)=1+frack(1-k)2 n+Oleft(frac1n^2right)$$






          share|cite|improve this answer









          $endgroup$












          • $begingroup$
            This has already a slight touch of overkill, hasn't it? :-)
            $endgroup$
            – trancelocation
            1 hour ago










          • $begingroup$
            @trancelocation. You are totally right for the limit. One of my manias is to always look at the approach to the limit. Have a look at matheducators.stackexchange.com/questions/8339/… . Cheers :-)
            $endgroup$
            – Claude Leibovici
            1 hour ago














          2












          2








          2





          $begingroup$

          $$a_n=fracn!n^k(n-k)! implies log(a_n)=log(n!)-k log(n)-log((n-k)!)$$



          Use Stirling approximation and continue with Taylor series to get
          $$log(a_n)=frack(1-k)2 n+Oleft(frac1n^2right)$$ Continue with Taylor
          $$a_n=e^log(a_n)=1+frack(1-k)2 n+Oleft(frac1n^2right)$$






          share|cite|improve this answer









          $endgroup$



          $$a_n=fracn!n^k(n-k)! implies log(a_n)=log(n!)-k log(n)-log((n-k)!)$$



          Use Stirling approximation and continue with Taylor series to get
          $$log(a_n)=frack(1-k)2 n+Oleft(frac1n^2right)$$ Continue with Taylor
          $$a_n=e^log(a_n)=1+frack(1-k)2 n+Oleft(frac1n^2right)$$







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered 1 hour ago









          Claude LeiboviciClaude Leibovici

          125k1158135




          125k1158135











          • $begingroup$
            This has already a slight touch of overkill, hasn't it? :-)
            $endgroup$
            – trancelocation
            1 hour ago










          • $begingroup$
            @trancelocation. You are totally right for the limit. One of my manias is to always look at the approach to the limit. Have a look at matheducators.stackexchange.com/questions/8339/… . Cheers :-)
            $endgroup$
            – Claude Leibovici
            1 hour ago

















          • $begingroup$
            This has already a slight touch of overkill, hasn't it? :-)
            $endgroup$
            – trancelocation
            1 hour ago










          • $begingroup$
            @trancelocation. You are totally right for the limit. One of my manias is to always look at the approach to the limit. Have a look at matheducators.stackexchange.com/questions/8339/… . Cheers :-)
            $endgroup$
            – Claude Leibovici
            1 hour ago
















          $begingroup$
          This has already a slight touch of overkill, hasn't it? :-)
          $endgroup$
          – trancelocation
          1 hour ago




          $begingroup$
          This has already a slight touch of overkill, hasn't it? :-)
          $endgroup$
          – trancelocation
          1 hour ago












          $begingroup$
          @trancelocation. You are totally right for the limit. One of my manias is to always look at the approach to the limit. Have a look at matheducators.stackexchange.com/questions/8339/… . Cheers :-)
          $endgroup$
          – Claude Leibovici
          1 hour ago





          $begingroup$
          @trancelocation. You are totally right for the limit. One of my manias is to always look at the approach to the limit. Have a look at matheducators.stackexchange.com/questions/8339/… . Cheers :-)
          $endgroup$
          – Claude Leibovici
          1 hour ago


















          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.




          draft saved


          draft discarded














          StackExchange.ready(
          function ()
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3185830%2fwhy-is-the-limit-of-this-expression-equal-to-1%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







          o DofXW,Qh,8,jHv,Hf8ruQDMAA XHnLcfA4orly9hfeTSq8POuQQrZZFTH,WrIKB,s0AU U9L 8Mk4LF4pA3j9gXP
          Eru5j16Lvt,m2,NV48RDpuQdFWNOcomPO39BYl3bDtAkvqsTu,2q5GcEuYF7J9ppaDET XUQrVqLOOl4f0IH382ZmdS7sDY0HrchG Pr

          Popular posts from this blog

          Creating centerline of river in QGIS? The 2019 Stack Overflow Developer Survey Results Are In Announcing the arrival of Valued Associate #679: Cesar Manara Planned maintenance scheduled April 17/18, 2019 at 00:00UTC (8:00pm US/Eastern)Finding centrelines from polygons in QGIS?Splitting line into two lines with GRASS GIS?Centroid of the equator and a pointpostgis: problems creating flow direction polyline; not all needed connections are drawnhow to make decent sense from scattered river depth measurementsQGIS Interpolation on Curved Grid (River DEMs)How to create automatic parking baysShortest path creation between two linesclipping layer using query builder in QGISFinding which side of closest polyline point lies on in QGIS?Create centerline from multi-digitized roadway lines Qgis 2.18Getting bathymetric contours confined only within river banks using QGIS?

          What is the result of assigning to std::vector::begin()? The Next CEO of Stack OverflowWhat are the differences between a pointer variable and a reference variable in C++?What does the explicit keyword mean?Concatenating two std::vectorsHow to find out if an item is present in a std::vector?Why is “using namespace std” considered bad practice?What is the “-->” operator in C++?What is the easiest way to initialize a std::vector with hardcoded elements?What is The Rule of Three?What are the basic rules and idioms for operator overloading?Why are std::begin and std::end “not memory safe”?