Is $sup_{xin mathbb R} sqrt{|x|} sin x = + infty$?












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The graph of $sqrt{|x|} sin x$ seems like staying around the $x$-axis, but $lim_{xto infty} sqrt{|x|} = +infty$ and $sin x$ is bounded.










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  • $begingroup$
    Perhaps a more interesting question is if you restrict $x$ to be an integer.
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    – MathematicsStudent1122
    Feb 1 at 5:53
















0












$begingroup$


The graph of $sqrt{|x|} sin x$ seems like staying around the $x$-axis, but $lim_{xto infty} sqrt{|x|} = +infty$ and $sin x$ is bounded.










share|cite|improve this question









$endgroup$












  • $begingroup$
    Perhaps a more interesting question is if you restrict $x$ to be an integer.
    $endgroup$
    – MathematicsStudent1122
    Feb 1 at 5:53














0












0








0





$begingroup$


The graph of $sqrt{|x|} sin x$ seems like staying around the $x$-axis, but $lim_{xto infty} sqrt{|x|} = +infty$ and $sin x$ is bounded.










share|cite|improve this question









$endgroup$




The graph of $sqrt{|x|} sin x$ seems like staying around the $x$-axis, but $lim_{xto infty} sqrt{|x|} = +infty$ and $sin x$ is bounded.







real-analysis analysis proof-explanation intuition






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asked Feb 1 at 5:47









user398843user398843

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  • $begingroup$
    Perhaps a more interesting question is if you restrict $x$ to be an integer.
    $endgroup$
    – MathematicsStudent1122
    Feb 1 at 5:53


















  • $begingroup$
    Perhaps a more interesting question is if you restrict $x$ to be an integer.
    $endgroup$
    – MathematicsStudent1122
    Feb 1 at 5:53
















$begingroup$
Perhaps a more interesting question is if you restrict $x$ to be an integer.
$endgroup$
– MathematicsStudent1122
Feb 1 at 5:53




$begingroup$
Perhaps a more interesting question is if you restrict $x$ to be an integer.
$endgroup$
– MathematicsStudent1122
Feb 1 at 5:53










1 Answer
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$begingroup$

Let $x = frac{pi}2 +2npi$,



Then, $$sqrt{|x|} sin x=sqrt{frac{pi}2+2npi}$$



Now, let $nto infty$ to get your result.






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    1 Answer
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    1 Answer
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    2












    $begingroup$

    Let $x = frac{pi}2 +2npi$,



    Then, $$sqrt{|x|} sin x=sqrt{frac{pi}2+2npi}$$



    Now, let $nto infty$ to get your result.






    share|cite|improve this answer









    $endgroup$


















      2












      $begingroup$

      Let $x = frac{pi}2 +2npi$,



      Then, $$sqrt{|x|} sin x=sqrt{frac{pi}2+2npi}$$



      Now, let $nto infty$ to get your result.






      share|cite|improve this answer









      $endgroup$
















        2












        2








        2





        $begingroup$

        Let $x = frac{pi}2 +2npi$,



        Then, $$sqrt{|x|} sin x=sqrt{frac{pi}2+2npi}$$



        Now, let $nto infty$ to get your result.






        share|cite|improve this answer









        $endgroup$



        Let $x = frac{pi}2 +2npi$,



        Then, $$sqrt{|x|} sin x=sqrt{frac{pi}2+2npi}$$



        Now, let $nto infty$ to get your result.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Feb 1 at 5:52









        Siong Thye GohSiong Thye Goh

        104k1468120




        104k1468120






























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