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Homework Help: Log question

  1. Jan 22, 2007 #1
    1. The problem statement, all variables and given/known data

    log base 5 cube root 25 equals what?


    2. Relevant equations

    I know that the answer is 2/3 because it is in the back of the book

    3. The attempt at a solution

    log base 5 = 25 to the 1/3

    so 5 to the what = 25 to the 1/3

    How do I get 5 to the 2/3 equals 25 to the 1/3? This is the only tough question in this section. :cry:
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Jan 22, 2007 #2
    write 25 to the 1/3 as 25^(1/3).
    but 25=5^2 so 25^(1/3)=(5^2)^(1/3). By your rules about exponents that is equal to 5^(2/3).
     
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