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Homework Help: Express as a single fraction n/(n-3) - n/(n+2)

  1. Jun 4, 2010 #1
    n/(n-3) - n/(n+2)

    I have tried to solve this by giving n a value. I chose n = 6, which gives:

    6/3 - 6/8

    The LCM of 3 and 8 is 24 so...

    6/3 - 6/8 = 48/24 - 18/24 which gives 30/24

    Final answer = 5/4

    Is that the correct answer and have I used the correct method of solving the problem?
     
  2. jcsd
  3. Jun 4, 2010 #2

    tiny-tim

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    Hi Gringo123! :smile:
    Sorry, but that's madness. :redface:

    The question is asking for p(n)/q(n), where p and q are both polynomials in n.

    (For example, 1/(n-1) + 1/(n+1) = 2n/(n2-1). :wink:)
     
  4. Jun 4, 2010 #3
    Yes for n=6 your solution is correct. But n can take few more values to get a fraction.
     
  5. Jun 4, 2010 #4
    I think I have it now
    ans = 5n / (n-3)(n+2)
     
  6. Jun 4, 2010 #5

    tiny-tim

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    Yup! :biggrin:
     
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