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Homework Help: Missing terms of a geometric seqeunce

  1. Jun 5, 2012 #1
    1. The problem statement, all variables and given/known data
    Write the first 5 terms of the geometric sequence
    3, __ , 32x+1, __, __

    2. Relevant equations
    tn=arn-1


    3. The attempt at a solution
    tn=arn-1
    32x+1=3r3-1
    r2=32x+1 / 3
    r=√32x+1 / √3

    I'm stuck
     
  2. jcsd
  3. Jun 6, 2012 #2
    Before taking the square root, try to simplyfy the right side. What is [itex]\frac{3^{2x+1}}{3^{1}}[/itex]?
     
  4. Jun 6, 2012 #3
    Hint:

    If [itex]a,b,c[/itex] are three consecutive terms of a geometric sequence, [itex]b^2 = ac[/itex].
     
  5. Jun 7, 2012 #4
    Ohh I see. 32x+1 / 31 = 32x. And the square root of that is 3x.
    Thank you
     
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