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    Just stuck on how to do this question!
    The sequences of terms U1, U2, U3... is defined by
    U1=8 Un+1=AUn +1 where a is a negative constant
    The third term of the sequence is U3=2.68
    Find the value of a

    Thankyou!


    ---Moved to Maths---
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    (Original post by Megan.Rose..)
    Just stuck on how to do this question!
    The sequences of terms U1, U2, U3... is defined by
    U1=8 Un+1=AUn +1 where a is a negative constant
    The third term of the sequence is U3=2.68
    Find the value of a

    Thankyou!
    Sticking to algebra, run through the formula until you get to n=3 writing out everything you see (brackets are your friend), You should be able to solve from there
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    (Original post by Megan.Rose..)
    Just stuck on how to do this question!
    The sequences of terms U1, U2, U3... is defined by
    U1=8 Un+1=AUn +1 where a is a negative constant
    The third term of the sequence is U3=2.68
    Find the value of a

    Thankyou!
    Can you find U_3 in terms of A?
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    (Original post by Megan.Rose..)
    Just stuck on how to do this question!
    The sequences of terms U1, U2, U3... is defined by
    U1=8 Un+1=AUn +1 where a is a negative constant
    The third term of the sequence is U3=2.68
    Find the value of a

    Thankyou!


    ---Moved to Maths---
    You should be able to get U_3 as a quadratic in A, and this will have one negative root which will be the value of A.
 
 
 
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