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Prove log4(18) irrational

  1. Oct 4, 2011 #1
    1. The problem statement, all variables and given/known data
    rational numbers are in form x/y

    2. Relevant equations
    logab = logcb / logca

    3. The attempt at a solution
    log218 / log218 = x/y
    (b) log218 = (a) log218
    log218b = log218a

    Then I am stuck.
  2. jcsd
  3. Oct 4, 2011 #2
    Sorry, the problem is prove that log(4)18 is irrational. I also realize that this should be done as a contradiction, I am just not sure how to do it.
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