- #1
NewtonianAlch
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Homework Statement
Evaluate the follow by first changing the order of integration
[tex]\int_{x=-1}^{1}\int_{y=x^2}^{2-x^2}dydx[/tex]
The Attempt at a Solution
This is the region we're concerned with:
http://www.wolframalpha.com/input/?i=plot%28y%3Dx^2%2C+y+%3D+2+-+x^2%2C+x%3D+1%2C+x%3D+-1%29
The new inequalities would be:
[itex]0 ≤ y ≤ 2 [/itex]
[itex]\sqrt {-y+2} ≤ x ≤ √y [/itex]
[tex]\int_{y=0}^{2}\int_{x=sqrt(-y + 2)}^{sqrt(y)}dxdy[/tex]
Doing this double integral gives me a final answer of zero which I checked on MAPLE. The correct answer is 8/3
I'm guessing the bounds are incorrect, but I can't figure out why. On the plot y clearly has a lower limit of 0 and an upper limit of 2. The limits of x I just manipulated through the previous inequality.