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Homework Help: Antiderivative of (x^2 + 4x)^(1/3)

  1. Mar 27, 2006 #1
    If f is the function defined by f(x) = (x^2 + 4x)^(1/3) and g is an antiderivative of f such that g(5) = 7 then g(1) =

    I thought that I need to find the antiderivative of f but it turns out that it's really messy so I'm not sure, is there something I'm missing to be able to solve for g(1)?
     
  2. jcsd
  3. Mar 27, 2006 #2
    You were on the right track. Find the anti derivative G, and add a constant, C. (Do you know why?) Now choose C such that G(5) = 7. Then find G(1) using the antiderivative plus the C you just found.
     
  4. Mar 27, 2006 #3

    arildno

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    You already KNOW that g is an anti-derivative of f!
    Now, how can you therefore represent g(1) in terms of g(5) and a definite integral of f?
     
  5. Mar 28, 2006 #4

    HallsofIvy

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    Do you want a numerical answer or would g(1)= a formula be sufficient? I think that is what arildno is saying.
     
  6. Mar 28, 2006 #5

    arildno

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    Agreed:
    I can't see any obvious way to evaluate the definite integral other than through numerical integration.
     
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