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Homework Help: Ugh, help

  1. Oct 27, 2004 #1
    Ok, I'm sure this is an easy problem and all, but it's pissing me off. I'm probably just not understanding it.

    The function f has the property that for any real numbers x and y, f(x+y)=f(x)+f(y)+1. If f(1)=2, what is f(3)?

  2. jcsd
  3. Oct 27, 2004 #2


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    Just use the information provided to find f(2) from which f(3) = 8 follows.
  4. Oct 27, 2004 #3
    wow... I feel completely lost.
    How do I find f(2)?
  5. Oct 27, 2004 #4


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    Gold Member


    If you are given that f(x+y)=f(x)+f(y)+1

    then it would be logical to conclude that

    f(1+1)=f(1)+f(1)+1 and I think you can take it from there
  6. Oct 27, 2004 #5
    Oh my.. Thanks. I'm such an idiot =)
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