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FP1 Tricky Series Question Watch

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    https://7cba9babeb0db0ff9468853e0b2d...%20Edexcel.pdf


    10 ii) I can't get the correct sereis expansion for n+1

    Can anyone help me out please
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    (Original post by Damien_Dalgaard)
    https://7cba9babeb0db0ff9468853e0b2d...%20Edexcel.pdf


    10 ii) I can't get the correct sereis expansion for n+1

    Can anyone help me out please
    Edit: Misleading - see below.
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    (Original post by SeanFM)
    Is it the 2n+1 bit you're referring to?

    If so, then think how you can express the series of (2n+1), splitting them up as you do for the other two terms in the original sum may help.

    Thank you for your reply, I am still unsure with the expansion of 2n+1, why is the n here not being expanded to (n/2)(n+1). :?

    Is (n+1) the last term it could be?
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    (Original post by Damien_Dalgaard)
    https://7cba9babeb0db0ff9468853e0b2d...%20Edexcel.pdf


    10 ii) I can't get the correct sereis expansion for n+1

    Can anyone help me out please
    Give me a few minutes

    EDIT: TSR APP SOOO SLOW, I should learn to use latex.
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    (Original post by Damien_Dalgaard)
    https://7cba9babeb0db0ff9468853e0b2d...%20Edexcel.pdf


    10 ii) I can't get the correct sereis expansion for n+1

    Can anyone help me out please
    Name:  ImageUploadedByStudent Room1431364230.290198.jpg
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    Enjoy and hope it helps!


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    (Original post by Damien_Dalgaard)
    Thank you for your reply, I am still unsure with the expansion of 2n+1, why is the n here not being expanded to (n/2)(n+1). :?

    Is (n+1) the last term it could be?
    Sorry, my post above is misleading and I see the (n+1) that you're talking about.

    The series is in terms of r, which changes, but n is a fixed constant (very sneaky). So when r = 0, you add on 2n and 1, when r = 1 you add on 2n +1 as well as r^2 - 2r.

    You would think it expands because it feels like it should be n=1, n=2 so you can sum it up, but it's always 'n' being added on.
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    (Original post by Jai Sandhu)
    Name:  ImageUploadedByStudent Room1431364230.290198.jpg
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    Enjoy and hope it helps!


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    (Original post by SeanFM)
    Sorry, my post above is misleading and I see the (n+1) that you're talking about.

    The series is in terms of r, which changes, but n is a fixed constant (very sneaky). So when r = 0, you add on 2n and 1, when r = 1 you add on 2n +1 as well as r^2 - 2r.

    You would think it expands because it feels like it should be n=1, n=2 so you can sum it up, but it's always 'n' being added on.
    Thank you both so much, this is incredibly helpful and I understand, prsom. Thank you for your detailed responses I really appreciate it
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    (Original post by Damien_Dalgaard)
    Thank you both so much, this is incredibly helpful and I understand, prsom. Thank you for your detailed responses I really appreciate it
    No worries! Good luck for your FP1 exam, if you need any help just message me.
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    (Original post by Jai Sandhu)
    No worries! Good luck for your FP1 exam, if you need any help just message me.

    Thank you so much, are you doing any maths a level exams
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    (Original post by Damien_Dalgaard)
    Thank you so much, are you doing any maths a level exams
    I am doing M2-3, S1-2, C3-4, FP1-3, STEP 1, AEA. All apart from last 2 are OCR


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    (Original post by Jai Sandhu)
    I am doing M2-3, S1-2, C3-4, FP1-3, STEP 1, AEA. All apart from last 2 are OCR


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    Impressive, I am doing FP1-FP2, C3-C4 M2 S2-S3

    With Edexcel though.

    Are STEP and AEA as difficult as everyone makes out?
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    (Original post by Damien_Dalgaard)
    Impressive, I am doing FP1-FP2, C3-C4 M2 S2-S3

    With Edexcel though.

    Are STEP and AEA as difficult as everyone makes out?
    STEP is certainly as difficult as it is made out to be however with rigorous practice over half a year you pick up trucks, strong algebra fluency and abilities which greatly aid you in the exam along with all other Maths exams. AEA is just a very very hard a level paper, I've only done 1 paper, will do a couple more in half term then do 10 or so in 3 days before the exam (it's my last one 4 days after my previous one). It isn't as hard in my opinion but it has high grade boundaries and many people don't take it seriously enough so don't do well. You can't afford to not answer any question in AEA whilst in step you pick 6 out of 13 so you can focus on strengths.


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    (Original post by Jai Sandhu)
    STEP is certainly as difficult as it is made out to be however with rigorous practice over half a year you pick up trucks, strong algebra fluency and abilities which greatly aid you in the exam along with all other Maths exams. AEA is just a very very hard a level paper, I've only done 1 paper, will do a couple more in half term then do 10 or so in 3 days before the exam (it's my last one 4 days after my previous one). It isn't as hard in my opinion but it has high grade boundaries and many people don't take it seriously enough so don't do well. You can't afford to not answer any question in AEA whilst in step you pick 6 out of 13 so you can focus on strengths.


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    I see good luck with it all, I am sure you will be fine with it all though. :yep:
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    (Original post by Damien_Dalgaard)
    I see good luck with it all, I am sure you will be fine with it all though. :yep:
    And good luck to you aswell
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    (Original post by SeanFM)
    Sorry, my post above is misleading and I see the (n+1) that you're talking about.

    The series is in terms of r, which changes, but n is a fixed constant (very sneaky). So when r = 0, you add on 2n and 1, when r = 1 you add on 2n +1 as well as r^2 - 2r.

    You would think it expands because it feels like it should be n=1, n=2 so you can sum it up, but it's always 'n' being added on.
    So if there's 3n^2 +2 we would add (3n^2 +2)(n+1) if it's from r=0?

    What if it's from r=1?


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    (Original post by Mutleybm1996)
    So if there's 3n^2 +2 we would add (3n^2 +2)(n+1) if it's from r=0?

    What if it's from r=1?


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    Yes

    If r = 1 then you have 1 less (3n^2 + 2).
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    (Original post by SeanFM)
    Yes

    If r = 1 then you have 1 less (3n^2 + 2).
    So it would simply by (n)(3n^2 + 2)?


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    (Original post by Mutleybm1996)
    So it would simply by (n)(3n^2 + 2)?


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    Yes.
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    Good luck everyone
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    (Original post by SeanFM)
    Edit: Misleading - see below.
    (Original post by Jai Sandhu)
    Name:  ImageUploadedByStudent Room1431364230.290198.jpg
Views: 496
Size:  132.3 KB

    Enjoy and hope it helps!


    Posted from TSR Mobile

    Thanks you guys, it really helped.

    This question didn't come up though haha nor did p.b.i for divisiblity :lol2:

    Hope it all went well
 
 
 
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