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    Hi I would need help with part 2 of this question, my answer looks quite unrealistic
    Thanks 🙏🏼
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    (Original post by Amarante)
    Hi I would need help with part 2 of this question, my answer looks quite unrealistic
    Thanks 🙏🏼
    Well, what's your answer? What did you do? Show us.
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    (Original post by Zacken)
    Well, what's your answer? What did you do? Show us.
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    As I said, looks unrealistic, I can't spot the mistake and I'm not sure if the application of the formula is correct when r is denominator
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    (Original post by Amarante)

    As I said, looks unrealistic, I can't spot the mistake and I'm not sure if the application of the formula is correct when r is denominator
    That's not right. You should apply the method of differences for \displaystyle \sum_{r=1}^n \frac{1}{r} - \frac{1}{r+1}
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    you cannot apply the formula for summation of x if it says 1/x
    instead put in numbers and see how the terms cancel.
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    (Original post by the bear)
    you cannot apply the formula for summation of x if it says 1/x
    instead put in numbers and see how the terms cancel.
    I'm lost, do I just substitute n when r is denominator?
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    you start off with r = 1, then 2, then 3, then 4, then 5,... then go to the end where r is n -1 , and finally n.

    you should look for a pattern of cancellations.
 
 
 
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