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Homework Help: May I get a comment on this proof?

  1. Oct 26, 2011 #1
    1. The problem statement, all variables and given/known data

    Prove directly:

    Prove that if [tex]2^{2x}[/tex] is odd integer, then [tex]4^{x}[/tex] is odd integer

    3. The attempt at a solution

    [tex]2^{2x} = 2k + 1[/tex] for some k is integer

    [tex]2^{2x} = 4^{x} = 2k + 1[/tex]

    Thus completes the proof?

    Am I allow to make the assumption (fact) [tex]2^{2x} = 4^{x}[/tex]?

  2. jcsd
  3. Oct 26, 2011 #2
    That is correct. It is indeed true that [itex]a^{bc}=(a^b)^c[/itex].
  4. Oct 26, 2011 #3
    nvm...I am just being an idiot
  5. Oct 26, 2011 #4
    That's okay, sometimes I get concerned when things are trivial too.
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