Compute $lim_nto infty frac1nsum_k=1^nleft(1+frackn^2right)^n$

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I want to compute $$lim_nto infty frac1nsum_k=1^nleft(1+frackn^2right)^n.$$
I really tried several thing, but this $frac1n^2$ annoy me very much. It looks like a Riemann sum, but I can't conclude without more information.







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    up vote
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    down vote

    favorite
    3












    I want to compute $$lim_nto infty frac1nsum_k=1^nleft(1+frackn^2right)^n.$$
    I really tried several thing, but this $frac1n^2$ annoy me very much. It looks like a Riemann sum, but I can't conclude without more information.







    share|cite|improve this question





















      up vote
      6
      down vote

      favorite
      3









      up vote
      6
      down vote

      favorite
      3






      3





      I want to compute $$lim_nto infty frac1nsum_k=1^nleft(1+frackn^2right)^n.$$
      I really tried several thing, but this $frac1n^2$ annoy me very much. It looks like a Riemann sum, but I can't conclude without more information.







      share|cite|improve this question











      I want to compute $$lim_nto infty frac1nsum_k=1^nleft(1+frackn^2right)^n.$$
      I really tried several thing, but this $frac1n^2$ annoy me very much. It looks like a Riemann sum, but I can't conclude without more information.









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      share|cite|improve this question




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      asked Jul 16 at 9:17









      user380364

      942214




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          1 Answer
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          Hint



          $$left(1+frackn^2right)^n=expleftnlnleft(1+frackn^2right)right.$$
          One can prove that $$x-fracx^22leq ln(1+x)leq x.$$



          Therefore, for all $kin1,...,n$,
          $$frackn-frac12nleq nlnleft(1+frackn^2right)leq frackn.$$



          The claim follow by composing and summing each side.






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            1 Answer
            1






            active

            oldest

            votes








            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes








            up vote
            4
            down vote



            accepted










            Hint



            $$left(1+frackn^2right)^n=expleftnlnleft(1+frackn^2right)right.$$
            One can prove that $$x-fracx^22leq ln(1+x)leq x.$$



            Therefore, for all $kin1,...,n$,
            $$frackn-frac12nleq nlnleft(1+frackn^2right)leq frackn.$$



            The claim follow by composing and summing each side.






            share|cite|improve this answer

























              up vote
              4
              down vote



              accepted










              Hint



              $$left(1+frackn^2right)^n=expleftnlnleft(1+frackn^2right)right.$$
              One can prove that $$x-fracx^22leq ln(1+x)leq x.$$



              Therefore, for all $kin1,...,n$,
              $$frackn-frac12nleq nlnleft(1+frackn^2right)leq frackn.$$



              The claim follow by composing and summing each side.






              share|cite|improve this answer























                up vote
                4
                down vote



                accepted







                up vote
                4
                down vote



                accepted






                Hint



                $$left(1+frackn^2right)^n=expleftnlnleft(1+frackn^2right)right.$$
                One can prove that $$x-fracx^22leq ln(1+x)leq x.$$



                Therefore, for all $kin1,...,n$,
                $$frackn-frac12nleq nlnleft(1+frackn^2right)leq frackn.$$



                The claim follow by composing and summing each side.






                share|cite|improve this answer













                Hint



                $$left(1+frackn^2right)^n=expleftnlnleft(1+frackn^2right)right.$$
                One can prove that $$x-fracx^22leq ln(1+x)leq x.$$



                Therefore, for all $kin1,...,n$,
                $$frackn-frac12nleq nlnleft(1+frackn^2right)leq frackn.$$



                The claim follow by composing and summing each side.







                share|cite|improve this answer













                share|cite|improve this answer



                share|cite|improve this answer











                answered Jul 16 at 9:24









                Surb

                36.3k84274




                36.3k84274






















                     

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