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    Hi,

    I am just stuck on the last few questions of logarithms, and was hoping you could help me answer them:

    How many terms are there in these geometric sequences:
    i) -1, 2, -4, 8, ... -16777216

    I know that the common ratio is multiply -2 each time, but thats as far as I got.

    ii) 0.1, 0.3, 0.9, 0.27, ... 4304672.1

    Again, I know the common ratio is x3.

    Soames Forstye states how many years it take to double your money at 7% interest. Given interest is paid yearly, at the end of the year, what number of years does he say?

    I dont really understand this question at all.

    Thank you for your help !!!
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    (Original post by cmab52)
    Hi,

    I am just stuck on the last few questions of logarithms, and was hoping you could help me answer them:

    How many terms are there in these geometric sequences:
    i) -1, 2, -4, 8, ... -16777216

    I know that the common ratio is multiply -2 each time, but thats as far as I got.

    ii) 0.1, 0.3, 0.9, 0.27, ... 4304672.1

    Again, I know the common ratio is x3.

    Soames Forstye states how many years it take to double your money at 7% interest. Given interest is paid yearly, at the end of the year, what number of years does he say?

    I dont really understand this question at all.

    Thank you for your help !!!
    un = ar^(n-1) = -16777216
    Where a = u1
    Same for part ii)
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    (Original post by cmab52)
    Hi,

    I am just stuck on the last few questions of logarithms, and was hoping you could help me answer them:

    How many terms are there in these geometric sequences:
    i) -1, 2, -4, 8, ... -16777216

    I know that the common ratio is multiply -2 each time, but thats as far as I got.

    ii) 0.1, 0.3, 0.9, 0.27, ... 4304672.1

    Again, I know the common ratio is x3.

    Soames Forstye states how many years it take to double your money at 7% interest. Given interest is paid yearly, at the end of the year, what number of years does he say?

    I dont really understand this question at all.

    Thank you for your help !!!
    Last q:
    Here a = 1
    r = 1.07
    you are trying to find when Sn>2
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    (Original post by joostan)
    un = ar^(n-1) = -16777216
    Where a = u1
    Same for part ii)
    Thank you!!
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    (Original post by cmab52)
    Thank you!!
    No problem
 
 
 
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