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    Yeah so I have this question

    First 3 terms of a geometric series are ( 3q +1) , (2q+2) , (2q-1) respectively, where q is a non-zero constant.

    how do i find the values of Q ? one is 5

    i was thinking because its a geometric sequence divide a term by its previous term and do simultaneos equation.

    2q+2 2q-1
    ------ = -------
    3q+1 2q+2

    But that didnt seem to work i got weird numbers like 3.4.23425.. etc when i know one of the values for Q is 5?

    can anyone help me out please ? thanks =]
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    Your method is correct, but you have written 3q-1 instead of 3q+1 in your fraction. I presume if you change this, you will be able to find the correct answer...
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    (Original post by Scott3142)
    Your method is correct, but you have written 3q-1 instead of 3q+1 in your fraction. I presume if you change this, you will be able to find the correct answer...
    woops, ignore my typo , I used the correct sign when i did the working on the paper, but i got strange answers, would you be able to write out the workings step by step?
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    Let a be the first term, r the common difference.

     a = 3q + 1

    ar = 2q + 2

    ar^2 = 2q - 1

    r = \frac{ar}{a} = \frac{ar^2}{ar}
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    ahaaa isee the error i made, thanks for your help =]
 
 
 
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