Analytical and/or Geometrical example of a certain function












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I need an example of a function that is continuous on some interval $I$, has a local minimum but doesn't have a global minimum. In other words, the problem of finding the global minimum of that function on an interval $I$ yields no solutions.



Does the function $Sinx^2, I=[-1;2)$ meet that condition?










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    $begingroup$


    I need an example of a function that is continuous on some interval $I$, has a local minimum but doesn't have a global minimum. In other words, the problem of finding the global minimum of that function on an interval $I$ yields no solutions.



    Does the function $Sinx^2, I=[-1;2)$ meet that condition?










    share|cite|improve this question









    $endgroup$















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      0








      0





      $begingroup$


      I need an example of a function that is continuous on some interval $I$, has a local minimum but doesn't have a global minimum. In other words, the problem of finding the global minimum of that function on an interval $I$ yields no solutions.



      Does the function $Sinx^2, I=[-1;2)$ meet that condition?










      share|cite|improve this question









      $endgroup$




      I need an example of a function that is continuous on some interval $I$, has a local minimum but doesn't have a global minimum. In other words, the problem of finding the global minimum of that function on an interval $I$ yields no solutions.



      Does the function $Sinx^2, I=[-1;2)$ meet that condition?







      optimization






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      asked Jan 26 at 19:02









      Nick202Nick202

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          Yes, $sin(x^2)$ on $[-1,2)$ would work. $x=0$ is a local minimum, at which the value is $0$, but there is no global minimum as it never attains the infimum value of $sin(4)$.






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            $begingroup$

            Yes, $sin(x^2)$ on $[-1,2)$ would work. $x=0$ is a local minimum, at which the value is $0$, but there is no global minimum as it never attains the infimum value of $sin(4)$.






            share|cite|improve this answer









            $endgroup$


















              0












              $begingroup$

              Yes, $sin(x^2)$ on $[-1,2)$ would work. $x=0$ is a local minimum, at which the value is $0$, but there is no global minimum as it never attains the infimum value of $sin(4)$.






              share|cite|improve this answer









              $endgroup$
















                0












                0








                0





                $begingroup$

                Yes, $sin(x^2)$ on $[-1,2)$ would work. $x=0$ is a local minimum, at which the value is $0$, but there is no global minimum as it never attains the infimum value of $sin(4)$.






                share|cite|improve this answer









                $endgroup$



                Yes, $sin(x^2)$ on $[-1,2)$ would work. $x=0$ is a local minimum, at which the value is $0$, but there is no global minimum as it never attains the infimum value of $sin(4)$.







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Jan 26 at 19:28









                Erik ParkinsonErik Parkinson

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