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Math Help - Find the area of the region by double integration

  1. #1
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    Find the area of the region by double integration

    The question states:

    Find the area of the region by double integration.

    The region inside the circle r=4cos(\Theta) but outside the circle r=2.

    I set up the problem with \int_{0}^{2\pi} \int_{2}^{4cos\Theta} rdrd\Theta

    However, the answer I got in the end was 4\pi, I'm assuming it's because of the way I set it up rather than a calculation error since I did it several times. The correct answer according to the textbook is 4\pi/3 +2\sqrt{3}.

    Thanks, any help would be appreciated.
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  2. #2
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    You're \theta limits are incorrect.
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  3. #3
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    Thank you very much, I figured out what the actual theta parameters are.
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