Thread: Evaluating Sums?

  1. #1
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    Evaluating Sums?

    Hello,
    I am currently working on a practice program in which I need to evaluate finite sums.


    Before I get to coding this, I need to understand how to do it on paper...

    Can someone please show me how I would go about evaluating this for example:

    2n
    E i
    i=5


    Step by step would appreciated b/c I am quite new to this whole concept.

    Thanks in advance~!

  2. #2
    Registered User Char*Pntr's Avatar
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    Quote Originally Posted by matthayzon89 View Post
    Hello,
    I am currently working on a practice program in which I need to evaluate finite sums.


    Before I get to coding this, I need to understand how to do it on paper...

    Can someone please show me how I would go about evaluating this for example:

    2n
    E i
    i=5


    Step by step would appreciated b/c I am quite new to this whole concept.

    Thanks in advance~!
    It's been a while since I've been in HS. I think the sum reduces to: n(2n + 1) with
    index i =1. (you have an offset 5)

    Before I go on, are you asking for help with the mathematics? If not, post the code
    that you have at this point.
    Last edited by Char*Pntr; 09-26-2010 at 11:49 AM. Reason: offset incorrect

  3. #3
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    Quote Originally Posted by Char*Pntr View Post
    It's been a while since I've been in HS. I think the sum reduces to: n(2n + 1) with
    index i =1. (you have an offset 5)

    Before I go on, are you asking for help with the mathematics? If not, post the code
    that you have at this point.

    Yes, I am working on the program. But I would like to understand how to work out the mathematics first, before I actually code up the problem.

    I appreciate your help man. It is really important that I understand this. I will most definitely study the explanation you will give, and would appreciate it if you can break it down to steps.

  4. #4
    Registered User Char*Pntr's Avatar
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    Unhappy

    Quote Originally Posted by matthayzon89 View Post
    Yes, I am working on the program. But I would like to understand how to work out the mathematics first, before I actually code up the problem.

    I appreciate your help man. It is really important that I understand this. I will most definitely study the explanation you will give, and would appreciate it if you can break it down to steps.
    I was hoping to help you get started, I still don't see any code yet.

    Since now this is a case of understanding the mathematics, this should have been
    posted in perhaps the General Discussion board.. np as this thread will probably be
    moved there anyway.

    I'm sorry, I can't as this is now completely off topic. This will only cause irritation to
    the regulars here, and rightly so.

  5. #5
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    Seems to me to be simple summation of i... up to 2n.

    So if n=6, i must reach 12 for the sequence to stop.

    answer is 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12

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