(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

See Figure.

2. Relevant equations

N/A

3. The attempt at a solution

Simplifying the double integral,

[tex]\int \int_{R} \sqrt{1 + 4x^2 + 4y^2} dA[/tex]

Am I suppose to put in the bounds for part a, as part of simplifying the integral?

This brings me to part b along with a few questions.

The whole point of this problem is to compute the area between the two circles mentioned above correct? I'm confused as to how this is done with double integrals.

If I wanted to find the area between the two circles I would simply find the area of the outer circle, [tex]x^2 + y^2 = 4[/tex] and subtract the area of the inner circle, [tex]x^2 + y^2 = 1[/tex].

That being said, wouldn't the natural geometrical interpretation of this simply be something like a doughnut?

I haven't gotten to part C yet, but I'd like to work out the misunderstandings I currently have and tackle that after.

Thanks again for the help!

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# Homework Help: Double Integral Question

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