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Please help me with a basic integration problem

  1. Jun 3, 2006 #1
    I have no idea what this means...
    Im taking a economics class and its been 4 years since I did any calculus work, and I am completely in awe at what im looking at here

    What do the symbols mean? How do you go from step 1 to step 2 to step 3?

    This is one tiny tiny bit of my course but ive been spending hours on it.. any help would be greatly appreciated :)

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  3. Jun 3, 2006 #2


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    Well, how much do you understand? Do you know elementary integrals, and are you familiar with the exponential and logarithmic functions?
  4. Jun 3, 2006 #3
    i can guess my way through basic elementary integrals
    Last edited: Jun 3, 2006
  5. Jun 3, 2006 #4
    what does "dx" mean?
  6. Jun 3, 2006 #5
    the change in x
  7. Jun 3, 2006 #6
  8. Jun 3, 2006 #7
    thanks all its making a lot more sense
    after you have integrated an integral, what do you do with it to 'solve' it using the upper and lower limits?
    for example, in the example the answer is e^ln(1+t) from 0 to n..
    how can i solve this now?
  9. Jun 3, 2006 #8


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    Gold Member

    See: Fundamental theorem of calculus (Scroll down to Formal Statements)

    Basically you evaluate your answer at n and from that subtract the answer evaluated at 0 if your limits happen to be 0 and n.
  10. Jun 5, 2006 #9


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    Also, do you see any way to simplify e^ln(1+t)? Hint: they're inverse functions.
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