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HELP PLEASE -Isomorphisms Really Hard

  1. Feb 11, 2009 #1
    Construct an isomorphism

    A4 (AND) D4 ---> (Z/2,+)X(Z/2,+)

    where D4's the symmetries of the square

    so I found D4(And)A4={(13)(24),Id,(12)(34),(14)(23)}
  2. jcsd
  3. Feb 12, 2009 #2


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    Science Advisor

    Then you are trying too hard! Map the identity to the identity of (Z/2,+)x(Z/2,+), (0,0). Then map (13)(24), (12)(34), (14)(23) to (0,1), (1,0), (1,1) any way you like. You will get an isomorphism.
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