Proving that $lim_{n to infty}t_n = s$











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I'm stuck on the following problem:




$s_n$ and $t_n$ are sequences, such that $s_n=t_n$ except for finitely many values of $n$. Explain why if $lim_{n rightarrow infty} s_n = s$, then also $lim_{n rightarrow infty}t_n = s$, using the definition of limit.




Actually, my problem is that I understand that thing, but I can't come up with the idea of using the definition (with $epsilon$ and $N$) to prove it.



Thank you in advance for any help!










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    up vote
    0
    down vote

    favorite












    I'm stuck on the following problem:




    $s_n$ and $t_n$ are sequences, such that $s_n=t_n$ except for finitely many values of $n$. Explain why if $lim_{n rightarrow infty} s_n = s$, then also $lim_{n rightarrow infty}t_n = s$, using the definition of limit.




    Actually, my problem is that I understand that thing, but I can't come up with the idea of using the definition (with $epsilon$ and $N$) to prove it.



    Thank you in advance for any help!










    share|cite|improve this question


























      up vote
      0
      down vote

      favorite









      up vote
      0
      down vote

      favorite











      I'm stuck on the following problem:




      $s_n$ and $t_n$ are sequences, such that $s_n=t_n$ except for finitely many values of $n$. Explain why if $lim_{n rightarrow infty} s_n = s$, then also $lim_{n rightarrow infty}t_n = s$, using the definition of limit.




      Actually, my problem is that I understand that thing, but I can't come up with the idea of using the definition (with $epsilon$ and $N$) to prove it.



      Thank you in advance for any help!










      share|cite|improve this question















      I'm stuck on the following problem:




      $s_n$ and $t_n$ are sequences, such that $s_n=t_n$ except for finitely many values of $n$. Explain why if $lim_{n rightarrow infty} s_n = s$, then also $lim_{n rightarrow infty}t_n = s$, using the definition of limit.




      Actually, my problem is that I understand that thing, but I can't come up with the idea of using the definition (with $epsilon$ and $N$) to prove it.



      Thank you in advance for any help!







      real-analysis






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      edited Oct 26 at 15:51









      Bungo

      13.5k22147




      13.5k22147










      asked Oct 26 at 15:18









      Sergey Malinov

      51




      51






















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          Since you know that $lim _{nto infty } s_n =s$, given a positive $epsilon$ you can find an $N$ such that $$nge N implies |s_n - s | < epsilon$$



          On the other hand you can find an $M$ such that $$ n>M implies s_n=t_n$$



          Let $K= max {N,M }$ and see what happens if $n>K$






          share|cite|improve this answer






























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            HINT



            Since $s_n=t_n$ except for finitely many values of $n$ a maximum value $bar n$ exixts such that $s_{bar n}neq t_{bar n}$.



            Then refer to the definition of limit.






            share|cite|improve this answer





















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              2 Answers
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              active

              oldest

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              2 Answers
              2






              active

              oldest

              votes









              active

              oldest

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              active

              oldest

              votes








              up vote
              0
              down vote



              accepted










              Since you know that $lim _{nto infty } s_n =s$, given a positive $epsilon$ you can find an $N$ such that $$nge N implies |s_n - s | < epsilon$$



              On the other hand you can find an $M$ such that $$ n>M implies s_n=t_n$$



              Let $K= max {N,M }$ and see what happens if $n>K$






              share|cite|improve this answer



























                up vote
                0
                down vote



                accepted










                Since you know that $lim _{nto infty } s_n =s$, given a positive $epsilon$ you can find an $N$ such that $$nge N implies |s_n - s | < epsilon$$



                On the other hand you can find an $M$ such that $$ n>M implies s_n=t_n$$



                Let $K= max {N,M }$ and see what happens if $n>K$






                share|cite|improve this answer

























                  up vote
                  0
                  down vote



                  accepted







                  up vote
                  0
                  down vote



                  accepted






                  Since you know that $lim _{nto infty } s_n =s$, given a positive $epsilon$ you can find an $N$ such that $$nge N implies |s_n - s | < epsilon$$



                  On the other hand you can find an $M$ such that $$ n>M implies s_n=t_n$$



                  Let $K= max {N,M }$ and see what happens if $n>K$






                  share|cite|improve this answer














                  Since you know that $lim _{nto infty } s_n =s$, given a positive $epsilon$ you can find an $N$ such that $$nge N implies |s_n - s | < epsilon$$



                  On the other hand you can find an $M$ such that $$ n>M implies s_n=t_n$$



                  Let $K= max {N,M }$ and see what happens if $n>K$







                  share|cite|improve this answer














                  share|cite|improve this answer



                  share|cite|improve this answer








                  edited 23 hours ago

























                  answered Oct 26 at 15:47









                  Mohammad Riazi-Kermani

                  40.2k41958




                  40.2k41958






















                      up vote
                      1
                      down vote













                      HINT



                      Since $s_n=t_n$ except for finitely many values of $n$ a maximum value $bar n$ exixts such that $s_{bar n}neq t_{bar n}$.



                      Then refer to the definition of limit.






                      share|cite|improve this answer

























                        up vote
                        1
                        down vote













                        HINT



                        Since $s_n=t_n$ except for finitely many values of $n$ a maximum value $bar n$ exixts such that $s_{bar n}neq t_{bar n}$.



                        Then refer to the definition of limit.






                        share|cite|improve this answer























                          up vote
                          1
                          down vote










                          up vote
                          1
                          down vote









                          HINT



                          Since $s_n=t_n$ except for finitely many values of $n$ a maximum value $bar n$ exixts such that $s_{bar n}neq t_{bar n}$.



                          Then refer to the definition of limit.






                          share|cite|improve this answer












                          HINT



                          Since $s_n=t_n$ except for finitely many values of $n$ a maximum value $bar n$ exixts such that $s_{bar n}neq t_{bar n}$.



                          Then refer to the definition of limit.







                          share|cite|improve this answer












                          share|cite|improve this answer



                          share|cite|improve this answer










                          answered Oct 26 at 15:39









                          gimusi

                          85.5k74294




                          85.5k74294






























                               

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