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For G = <a: a^100 = e>, find the following

  1. Oct 31, 2014 #1
    It's asking me to find a^-5
    From what I understood about inverses is that it's the element before you hit the identity would be the inverse. So a^5 = (a^5, a^10, a^15,..., a^90, a^95, a^100 = e), then a^-5 = a^95.

    The correct answer is actually a^20.

    Can anyone help me out with understanding inverses? Thanks!
  2. jcsd
  3. Oct 31, 2014 #2
    Nevermind, it was a typo. The answer was a^-5 = a^95
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