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F(x) substitution

  1. Aug 29, 2008 #1
    1. The problem statement, all variables and given/known data
    f(h+1)-f(h)/h. If f(x)=1/x, simplify.

    2. Relevant equations

    3. The attempt at a solution

    is the answer 1/h? I am not sure if i substituted this correctly or if I solved this right.
    I put 1/x in everywhere there was a f(h).
  2. jcsd
  3. Aug 29, 2008 #2


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    If f(x)=1/x, then f(h+1)=1/(h+1), f(5)=1/5. Etc. x is only a dummy variable.
  4. Aug 29, 2008 #3





  5. Aug 29, 2008 #4
    so it should have been (1/x+1 -1/x)/h
    dealing with the numerator first, I bring the terms to a common denominator..
    i multiply the numerator by 1/h and get..
    is that right?
  6. Aug 29, 2008 #5


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    You aren't listening. There are NO x's in (f(h+1)-f(h))/h. Reread the previous posts. By the way, are you sure the problem isn't (f(h+1)-f(1))/h??
    Last edited: Aug 29, 2008
  7. Aug 29, 2008 #6
    Okay, I can see that now. Thanks.
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