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Homework Help: Logarithm Issue. Unable to find answer sheet answer

  1. May 8, 2015 #1
    1. The problem statement, all variables and given/known data
    log39x4 - log3(3x)2

    The answer sheet says that the answer is 0, but when I work the problem both ways I get:

    Any ideas?

    2. Relevant equations
    logxy/z = logxy - logxz

    3. The attempt at a solution
    Formula Sheet
    20-30 Minutes of Messing around with the problem
  2. jcsd
  3. May 8, 2015 #2
    But ##(3x^2)^2=9x^4##..................
    [Edit:- so yeah either you typed the question wrong or the answer cannot be 0.]
  4. May 8, 2015 #3
    I typed it correctly. That's what I thought, but I assumed I must be going crazy or something :| Strange...
  5. May 8, 2015 #4
    Then your answer is correct :-)
  6. May 8, 2015 #5

    Ray Vickson

    User Avatar
    Science Advisor
    Homework Helper

    The formatting of the question is not entirely clear. Do you mean
    [tex] \log_3 (9x^4) - \log_3 ((3x)^2)\:?[/tex]
    If so, your answer is correct.

    Perhaps the person setting the question meant something else, but I cannot imagine what.
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