Show that $| x |^2_2 | x|_{2k-2}^{2k-2} leq n^{1-2/k} | x |^{2k}_k$












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$begingroup$


Let $x$ be in $R^n$. Show that:



$$| x |^2_2 cdot | x|_{2k-2}^{2k-2} leq n^{1-2/k} cdot | x |^{2k}_k~.$$










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    1












    $begingroup$


    Let $x$ be in $R^n$. Show that:



    $$| x |^2_2 cdot | x|_{2k-2}^{2k-2} leq n^{1-2/k} cdot | x |^{2k}_k~.$$










    share|cite|improve this question









    $endgroup$















      1












      1








      1





      $begingroup$


      Let $x$ be in $R^n$. Show that:



      $$| x |^2_2 cdot | x|_{2k-2}^{2k-2} leq n^{1-2/k} cdot | x |^{2k}_k~.$$










      share|cite|improve this question









      $endgroup$




      Let $x$ be in $R^n$. Show that:



      $$| x |^2_2 cdot | x|_{2k-2}^{2k-2} leq n^{1-2/k} cdot | x |^{2k}_k~.$$







      inequality






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      asked Jan 10 at 5:52









      HTVHTV

      1017




      1017






















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          $begingroup$

          Ok, I figured out the answer.



          We have



          $$| x |_2 leq n^{1/2-1/k} | x |_k implies | x |_2^2 leq n^{1-2/k} | x |_k^2~.$$



          See Relations between p norms for the first inequality. Also,



          $$| x|_{2k-2} leq | x |_k implies | x_{2k-2} |^{2k-2}_{2k-2} leq | x |_k^{2k-2} ~$$



          And we are done.






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            $begingroup$

            Ok, I figured out the answer.



            We have



            $$| x |_2 leq n^{1/2-1/k} | x |_k implies | x |_2^2 leq n^{1-2/k} | x |_k^2~.$$



            See Relations between p norms for the first inequality. Also,



            $$| x|_{2k-2} leq | x |_k implies | x_{2k-2} |^{2k-2}_{2k-2} leq | x |_k^{2k-2} ~$$



            And we are done.






            share|cite|improve this answer











            $endgroup$


















              1












              $begingroup$

              Ok, I figured out the answer.



              We have



              $$| x |_2 leq n^{1/2-1/k} | x |_k implies | x |_2^2 leq n^{1-2/k} | x |_k^2~.$$



              See Relations between p norms for the first inequality. Also,



              $$| x|_{2k-2} leq | x |_k implies | x_{2k-2} |^{2k-2}_{2k-2} leq | x |_k^{2k-2} ~$$



              And we are done.






              share|cite|improve this answer











              $endgroup$
















                1












                1








                1





                $begingroup$

                Ok, I figured out the answer.



                We have



                $$| x |_2 leq n^{1/2-1/k} | x |_k implies | x |_2^2 leq n^{1-2/k} | x |_k^2~.$$



                See Relations between p norms for the first inequality. Also,



                $$| x|_{2k-2} leq | x |_k implies | x_{2k-2} |^{2k-2}_{2k-2} leq | x |_k^{2k-2} ~$$



                And we are done.






                share|cite|improve this answer











                $endgroup$



                Ok, I figured out the answer.



                We have



                $$| x |_2 leq n^{1/2-1/k} | x |_k implies | x |_2^2 leq n^{1-2/k} | x |_k^2~.$$



                See Relations between p norms for the first inequality. Also,



                $$| x|_{2k-2} leq | x |_k implies | x_{2k-2} |^{2k-2}_{2k-2} leq | x |_k^{2k-2} ~$$



                And we are done.







                share|cite|improve this answer














                share|cite|improve this answer



                share|cite|improve this answer








                edited Jan 10 at 6:33

























                answered Jan 10 at 6:28









                HTVHTV

                1017




                1017






























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