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Homework Help: Find the area under this graph by integration (it's a simple function!)

  1. May 3, 2010 #1
    1. The problem statement, all variables and given/known data

    This is the function:
    y= 360(1.0297^x)
    Find the area between x=24, and x=48.
    The graph looks like this: http://tinypic.com/r/30w4bjp/5

    And the points are:
    24, 740.8379
    30, 883.0544
    36, 1052.572
    42, 1254.631
    48, 1495.479

    ASAP svp. =]

    2. Relevant equations
    Ah... You know it =/

    3. The attempt at a solution
    Unfortunately, I haven't learned integration. But I'm working on a Math IA (Internal Assessment) and I want to do this with a slightly higher quality. I just did some research but it's Greek to me so far =/
    Can someone calculate this please? I'd like to see maybe 2 or 3 steps to try and understand how you did it.
  2. jcsd
  3. May 3, 2010 #2


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    Homework Helper

    If you don't know integration, do you know any method to approximate the area? It will make no sense to try to explain the integration to you if you don't know what integration is in the first place.
  4. May 3, 2010 #3
    well I got 25299.6908 with Trapazoidal Approximation and 25105.80447 using Simpson's Rule but I can not tell you the error rate on either number because I don't know how to take the derivatives of that function. Contrary to what you might think it is not an elementary function. I can tell you that the number using Simpson's Rule is closer to the actual result than the trapazoidal approximation but I can't tell you how close....

    I got those using dx = 2, so if i took a smaller dx it would be better as well, but I don't want to spend the time doing all those calculations....
  5. May 3, 2010 #4


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    Homework Helper

    Actually, that integral can be solved using a substitution.
  6. May 3, 2010 #5
    really? I tried that but i couldn't get anything to come out, what is the substitution then? what does u =?
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