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Math Help - Sequences

  1. #1
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    Sequences

    OKay so i did not get this question. And i will appreciate it if someone tells me how to do it.

    use the given two terms of each geometric sequences to write the expression to the nth term:

    Term 4 = 45 Term 6= 180

    There is some application involved and it involves linear systems.

    So thanks!
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  2. #2
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by PMPowns View Post
    OKay so i did not get this question. And i will appreciate it if someone tells me how to do it.

    use the given two terms of each geometric sequences to write the expression to the nth term:

    Term 4 = 45 Term 6= 180

    There is some application involved and it involves linear systems.

    So thanks!
    the nth term of a geometric series is given by: a_n = ar^{n - 1} for n \in \mathbb{N} = \{ 1,2,3,4, ... \}

    where a is the first term, and r is the common ratio

    thus, a_4 = ar^3 = 45

    and a_6 = ar^5 = 180

    thus we have two simultaneous equations here, we can solve for a and r. then we can plug that into the general form to find the nth term

    can you continue?
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  3. #3
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    Thx alot, and yes i can continue. Amazing.
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