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Homework Help: Simple group theory question.

  1. Nov 16, 2006 #1
    Let G be a group. Let 'a' be an element of G. Let e be the identity of G Prove that if a = a^-1 then a^2= e.

    Is the proof below correct ?
    Suppose a = a^-1. Then

    a^2 = aa = a(a^-1) = e.
  2. jcsd
  3. Nov 16, 2006 #2
    yeah, if a is it's own inverse then a^2 is e. your proof looks fine to me.
  4. Nov 16, 2006 #3
    Thxs. He he he :!!)
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