Is $sqrt{x^3}$ uniformly continuous?











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$f(x) = sqrt{x^3}, x in (2,3)$ and $ g(x) = x^3, x in Bbb R$.



I have showed that $g$ is not uniformly continuous, but unable to do the 1st one i.e. $f(x) = sqrt{x^3}, x in (2,3)$.



Need some help for that part!










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  • Do you know differentiation / the mean value theorem? That will be helpful.
    – астон вілла олоф мэллбэрг
    Nov 17 at 11:37

















up vote
1
down vote

favorite












$f(x) = sqrt{x^3}, x in (2,3)$ and $ g(x) = x^3, x in Bbb R$.



I have showed that $g$ is not uniformly continuous, but unable to do the 1st one i.e. $f(x) = sqrt{x^3}, x in (2,3)$.



Need some help for that part!










share|cite|improve this question






















  • Do you know differentiation / the mean value theorem? That will be helpful.
    – астон вілла олоф мэллбэрг
    Nov 17 at 11:37















up vote
1
down vote

favorite









up vote
1
down vote

favorite











$f(x) = sqrt{x^3}, x in (2,3)$ and $ g(x) = x^3, x in Bbb R$.



I have showed that $g$ is not uniformly continuous, but unable to do the 1st one i.e. $f(x) = sqrt{x^3}, x in (2,3)$.



Need some help for that part!










share|cite|improve this question













$f(x) = sqrt{x^3}, x in (2,3)$ and $ g(x) = x^3, x in Bbb R$.



I have showed that $g$ is not uniformly continuous, but unable to do the 1st one i.e. $f(x) = sqrt{x^3}, x in (2,3)$.



Need some help for that part!







real-analysis continuity






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asked Nov 17 at 11:31









user8795

5,57961846




5,57961846












  • Do you know differentiation / the mean value theorem? That will be helpful.
    – астон вілла олоф мэллбэрг
    Nov 17 at 11:37




















  • Do you know differentiation / the mean value theorem? That will be helpful.
    – астон вілла олоф мэллбэрг
    Nov 17 at 11:37


















Do you know differentiation / the mean value theorem? That will be helpful.
– астон вілла олоф мэллбэрг
Nov 17 at 11:37






Do you know differentiation / the mean value theorem? That will be helpful.
– астон вілла олоф мэллбэрг
Nov 17 at 11:37












2 Answers
2






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up vote
4
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accepted










$f$ (same formula) is continuous on $[2,3]$ hence uniformly continuous on it (by compactness of $[2,3]$) and its subspaces (by definition uniform continuity inherits to subspaces).






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    Hint. Any function which is continuous in a compact set is also uniformly continuous there and in any of its subsets.






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      2 Answers
      2






      active

      oldest

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      2 Answers
      2






      active

      oldest

      votes









      active

      oldest

      votes






      active

      oldest

      votes








      up vote
      4
      down vote



      accepted










      $f$ (same formula) is continuous on $[2,3]$ hence uniformly continuous on it (by compactness of $[2,3]$) and its subspaces (by definition uniform continuity inherits to subspaces).






      share|cite|improve this answer

























        up vote
        4
        down vote



        accepted










        $f$ (same formula) is continuous on $[2,3]$ hence uniformly continuous on it (by compactness of $[2,3]$) and its subspaces (by definition uniform continuity inherits to subspaces).






        share|cite|improve this answer























          up vote
          4
          down vote



          accepted







          up vote
          4
          down vote



          accepted






          $f$ (same formula) is continuous on $[2,3]$ hence uniformly continuous on it (by compactness of $[2,3]$) and its subspaces (by definition uniform continuity inherits to subspaces).






          share|cite|improve this answer












          $f$ (same formula) is continuous on $[2,3]$ hence uniformly continuous on it (by compactness of $[2,3]$) and its subspaces (by definition uniform continuity inherits to subspaces).







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered Nov 17 at 11:37









          Henno Brandsma

          102k344108




          102k344108






















              up vote
              1
              down vote













              Hint. Any function which is continuous in a compact set is also uniformly continuous there and in any of its subsets.






              share|cite|improve this answer



























                up vote
                1
                down vote













                Hint. Any function which is continuous in a compact set is also uniformly continuous there and in any of its subsets.






                share|cite|improve this answer

























                  up vote
                  1
                  down vote










                  up vote
                  1
                  down vote









                  Hint. Any function which is continuous in a compact set is also uniformly continuous there and in any of its subsets.






                  share|cite|improve this answer














                  Hint. Any function which is continuous in a compact set is also uniformly continuous there and in any of its subsets.







                  share|cite|improve this answer














                  share|cite|improve this answer



                  share|cite|improve this answer








                  edited Nov 17 at 13:31

























                  answered Nov 17 at 11:39









                  Robert Z

                  91.1k1058129




                  91.1k1058129






























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