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Homework Help: Indices problem

  1. Dec 16, 2009 #1
    1. The problem statement, all variables and given/known data
    The problem is 4 x+ 3*2 x+2 + 32 = 0

    2. Relevant equations
    None


    3. The attempt at a solution
    I can’t get to any solution in this problem but I have come to a point (if it is nearing any solution though) but I am not sure whether it is correct or not.
    Well what I have done is
    2 2x + (2+1)2 x+2 + 2 5=0
    ==> 2 2x + 2*2 x+2 + 2 x+2 +2 5=0
    ==>2 2x + 2 x+3 + 2 x+2 +2 5=0
    ( That’s all I have done)
    I would be very thankful to receive any help!!
    Thank you!!
     
    Last edited: Dec 16, 2009
  2. jcsd
  3. Dec 16, 2009 #2

    Mark44

    Staff: Mentor

    4x = (22)x = 22x and 2x + 2 = 22* 2x

    Your equation can be rewritten so that it is quadratic in form.
     
  4. Dec 16, 2009 #3
    Ok so I write it like this
    2 2x + 2 x*2 3 + 2 x *2 2 +2 5=0
    But where does it go after this??
     
  5. Dec 16, 2009 #4
    you see, that 2^x is the common variable,
    so you can solve it like solving quadratic equation..

    or if you wan to see it more clearly, try let u = 2^x
     
  6. Dec 16, 2009 #5

    Mark44

    Staff: Mentor

    your coefficient of 2x is wrong. There should be only a single 2x term, not two of them as you show. 3*2x+2 does NOT expand to a sum of two terms.

    Also, rewriting 32 as 25 does you no good.
     
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