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Solving for Log Base

  1. Jan 13, 2009 #1
    1. The problem statement, all variables and given/known data

    3 = Log2x 64

    2. Relevant equations
    N/a


    3. The attempt at a solution

    3 = Log2x 64
    2x3 = 64
    x3 = 32
    x = Cubic root of 32
    x = 3.1748

    I'm fairly certain the answer has to be 2 b/c 2x would be equal to 4, and 43 = 64.

    Anyone mind helping me on this one? Probably a really simple error.
     
  2. jcsd
  3. Jan 13, 2009 #2
    (2x)3 not 2*x3

    Hover: your logic is flawed in that it omits the log
     
  4. Jan 13, 2009 #3
    As Saladsamurai said, the entire (2x) term would be cubed. The resulting answer is then 256, which is too much obviously.
     
  5. Jan 13, 2009 #4
    [itex](2x)^3=64\Rightarrow 2^3*x^3=64\Rightarrow 8x^3=64\Rightarrow x^3=8\Rightarrow x=2[/itex]

    We okay now? :smile:
     
  6. Jan 13, 2009 #5
    Yep, understand. Thank you :)
     
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