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Homework Help: Peicewise integral

  1. Apr 26, 2010 #1
    1. The problem statement, all variables and given/known data
    Evaluate the integral

    3. The attempt at a solution
    I tried splitting it into two integrals and adding the results, but it says that's wrong. I think it has something to do with the fact that the first part doesn't go all the way to zero...
  2. jcsd
  3. Apr 26, 2010 #2


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    Homework Helper

    Splitting up the integral is the correct approach. Show your work so people can see where you go wrong.
  4. Apr 26, 2010 #3
    Ok, so I started by evaluating the first function on the interval [-2,0]



    Then I evaluated the second function on [0,4]

    F(x)= 5x-x3/3

    Adding them gets me 2.6666666, which apparently is incorrect.
  5. Apr 26, 2010 #4


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    Why do you say it is apparently incorrect. Does the book provide an answer or do you enter it in some kind of computer program? Either way your answer is essentially correct, but since you've chosen to use decimals you get rounding errors. Use fractions instead.
  6. Apr 26, 2010 #5
    It is a computer program. I'll try with factions, it is very finicky sometimes...
  7. Apr 26, 2010 #6
    Entered 8/3 and was right. Hate computers! haha
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