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Homework Help: Easy factoring problem .I think

  1. Feb 4, 2012 #1
    Easy factoring problem.....I think


    So I'm working through how to do RSA encoding, but I've stumbled on something very simple in terms of factoring. All I pretty much want to know is:

    How do I factor: pq-p-q+1

    To get: (p-1)(q-1)

    Expanding it isn't the problem....what little trick am I missing.

  2. jcsd
  3. Feb 4, 2012 #2


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    Re: Easy factoring problem.....I think

    Factor p from the first two terms. Factor -1 from the last two terms.
  4. Feb 4, 2012 #3
    Re: Easy factoring problem.....I think

    ***Head slap***.....smh. Thanks.
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