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Homework Help: Problem sheet double integration

  1. Jan 19, 2010 #1
    1. The problem statement, all variables and given/known data

    [tex]\int\int x^3(x^2+y^2)[/tex] dy dx limts of x between 2 and -4 and y limits between 5 and 0

    2. Relevant equations

    3. The attempt at a solution

    i get an answer -17426 2/3 which doesn't seem right

    plugged the formula into maple and has given me an answer of -5860.

    my first step was to expand the brackets.

    to get [tex]\int\int x^5 + x^3y^2[/tex] then integrate with respect to dy. put the limits of y in as 5 and 0.

    [tex]\int 5x^5 + (125x^3/3)[/tex]
    then integrate with respect to x and again put the limits in.
  2. jcsd
  3. Jan 19, 2010 #2


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    Homework Helper

    I agree with Maple. I also agree with your x integration. Except I would put a minus sign in front because I integrated with a lower y limit of 5 and an upper y limit of 0. Is that what you meant? You'll have to show more intermediate results to be able to tell what you are doing wrong.
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