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Homework Help: Short yet confusing log equation

  1. Jan 3, 2009 #1
    1. The problem statement, all variables and given/known data
    Solve the equation
    log x4 - log x3 = log 3x - log 2x

    I know the laws of logs and I cleared all the other log questions in seconds but I cant figure this one out

    2. Relevant equations
    I know that log x4 - log x3 is the same as log x4/x3
    but what I was wondering is if I can use the laws of indices here and substract 3 from the 4 leaving me with log x

    3. The attempt at a solution
    Im completely stuck on this one
  2. jcsd
  3. Jan 3, 2009 #2


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    Homework Helper

    Yes you can.
  4. Jan 3, 2009 #3


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    Gold Member

    Yes, use a similar rule on the other side to solve the equation.
  5. Jan 3, 2009 #4
    I'm still stuck. So I put the equation in this format logx = log(3x/2x) then cancel out those x's so I have logx = log3/2. Do I just get rid of the logs and say x = 3/2?

    EDIT: I thought about that there and realized that obviously is the case. Thanks for the help
  6. Jan 3, 2009 #5


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    Gold Member

    Good Job!
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