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Homework Help: Please solve for x in this logarithmic equation? 4^x + 2^(x+1) = 60

  1. Jan 5, 2010 #1
    1. The problem statement, all variables and given/known data
    4x + 2(x+1) = 60


    2. Relevant equations
    N/A

    3. The attempt at a solution
    4x + 2(x+1) = 60
    22x + 2(x+1) = 60

    I don't know where to go from there.
     
  2. jcsd
  3. Jan 6, 2010 #2

    Mentallic

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    edit: ehild has the correct solution.
     
    Last edited: Jan 6, 2010
  4. Jan 6, 2010 #3

    ehild

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    You are on the right track. Note that [itex]2^{(x+1)}=2\cdot 2^x[/itex] and [itex]2^{2x}= (2^x)^2[/itex]. Then choose 2^x as new variable and solve the resultant second order equation.

    ehild
     
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