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    https://917c8db4f385e20466384eff57d8...%20Edexcel.pdf

    How do you do question 6d? June 2013 R paper

    
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    You do 50 times a2 plus 50 times 1 the answer should be 25
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    (Original post by jenqo)
    https://917c8db4f385e20466384eff57d8...%20Edexcel.pdf

    How do you do question 6d? June 2013 R paper

    
    Wait I don't think you can do the above way because the sequence doesn't have a common difference as such, or rather it just switches between two values.

    You should know from parts a b c that U1 = 1, U2 = 1-K (you'll have a number but I couldn't be bothered working it out) and U3 = 1. We have already seen that if you put 1 into the recurrence relation formula you get out 1-K so U4 must be 1-K and this in turn means U5 = 1... This means that all the 50 even terms are 1 and the 50 odd terms are all 1-K. Therefore to find the total you'd add 50 + 50(1-K)
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    Btw was K 3/2? Didn't work it out I just think I remember it being that... Also I think I remember the answer being 25?
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    (Original post by jenqo)
    https://917c8db4f385e20466384eff57d8...%20Edexcel.pdf

    How do you do question 6d? June 2013 R paper

    
    Here you go
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    (Original post by #sarahsmith2)
    Wait I don't think you can do the above way because the sequence doesn't have a common difference as such, or rather it just switches between two values.

    You should know from parts a b c that U1 = 1, U2 = 1-K (you'll have a number but I couldn't be bothered working it out) and U3 = 1. We have already seen that if you put 1 into the recurrence relation formula you get out 1-K so U4 must be 1-K and this in turn means U5 = 1... This means that all the 50 even terms are 1 and the 50 odd terms are all 1-K. Therefore to find the total you'd add 50 + 50(1-K)
    Spoiler:
    Show
    Btw was K 3/2? Didn't work it out I just think I remember it being that... Also I think I remember the answer being 25?
    Thank you very much
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    (Original post by JohnJ100)
    Here you go
    Bless you, I really appreciate it
 
 
 
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