Dual cone of a closed convex cone












1












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I am reading materials about convex optimizations. It says: If $Z$ is a closed convex cone, then $Z$ is the anti-dual of its anti-dual cone $Z_-$, i.e.,



$$
Z={zin mathbf{R}^{L+1}:z^Tzetaleq0,forallzetain Z_-},
$$

$$
Z_-={zetainmathbf{R}^{L+1}:zeta^Tzleq0,forall zin Z}.
$$



How can I prove this? Why is this property useful?










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migrated from stats.stackexchange.com Dec 13 '18 at 20:34


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    1












    $begingroup$


    I am reading materials about convex optimizations. It says: If $Z$ is a closed convex cone, then $Z$ is the anti-dual of its anti-dual cone $Z_-$, i.e.,



    $$
    Z={zin mathbf{R}^{L+1}:z^Tzetaleq0,forallzetain Z_-},
    $$

    $$
    Z_-={zetainmathbf{R}^{L+1}:zeta^Tzleq0,forall zin Z}.
    $$



    How can I prove this? Why is this property useful?










    share|cite|improve this question









    $endgroup$



    migrated from stats.stackexchange.com Dec 13 '18 at 20:34


    This question came from our site for people interested in statistics, machine learning, data analysis, data mining, and data visualization.





















      1












      1








      1


      2



      $begingroup$


      I am reading materials about convex optimizations. It says: If $Z$ is a closed convex cone, then $Z$ is the anti-dual of its anti-dual cone $Z_-$, i.e.,



      $$
      Z={zin mathbf{R}^{L+1}:z^Tzetaleq0,forallzetain Z_-},
      $$

      $$
      Z_-={zetainmathbf{R}^{L+1}:zeta^Tzleq0,forall zin Z}.
      $$



      How can I prove this? Why is this property useful?










      share|cite|improve this question









      $endgroup$




      I am reading materials about convex optimizations. It says: If $Z$ is a closed convex cone, then $Z$ is the anti-dual of its anti-dual cone $Z_-$, i.e.,



      $$
      Z={zin mathbf{R}^{L+1}:z^Tzetaleq0,forallzetain Z_-},
      $$

      $$
      Z_-={zetainmathbf{R}^{L+1}:zeta^Tzleq0,forall zin Z}.
      $$



      How can I prove this? Why is this property useful?







      optimization convex-analysis






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Dec 11 '18 at 8:10









      EggplantEggplant

      61




      61




      migrated from stats.stackexchange.com Dec 13 '18 at 20:34


      This question came from our site for people interested in statistics, machine learning, data analysis, data mining, and data visualization.









      migrated from stats.stackexchange.com Dec 13 '18 at 20:34


      This question came from our site for people interested in statistics, machine learning, data analysis, data mining, and data visualization.
























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