Problem sheet double integration

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Homework Statement



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

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

\int 5x^5 + (125x^3/3)
then integrate with respect to x and again put the limits in.
 
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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.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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