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Homework Help: Logarithms solving for x

  1. Jun 11, 2008 #1
    Solve the equation log2x + log4x= 5. To start, should I change this to an exponential.... I am stuck because I have only done log questions that have the same base.
     
  2. jcsd
  3. Jun 11, 2008 #2

    Dick

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    Convert them to the same base log_a(x)=log_b(x)/log_b(a).
     
  4. Jun 12, 2008 #3

    HallsofIvy

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    What do you mean by "log2x+ log4x= 5"? I would interpret that as log(2x)+ log(4x)= 5 so log(6x)= 5 which is easy. If you mean "log_2(x)+ log_4(x)= 5" then use Dick's hint.
    log_4(x)= log_2(x)/log_2(4)= ?
     
    Last edited by a moderator: Jun 12, 2008
  5. Aug 19, 2008 #4
    can u help solving a problem????
     
  6. Aug 19, 2008 #5
    can u help solve a problem???
     
  7. Aug 19, 2008 #6

    Dick

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    Can u post the problem? Under Forum Tools, "Post a New Thread". That's your first step.
     
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