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

I want to perform the following integration:

double integral of [(x^2)-(y^2)+2] dxdy where the function is subjected to the bound (x^2)+(y^2) greater than or equal to 2.

I'm trying to find the flux of a surface of a sphere (x^2)+(y^2)+(z^2)=9.

2. Relevant equations

Nothing, just rules of integration.

3. The attempt at a solution

Using Cartesian coordinates seems far too difficult. I could show you my work, but it's messy and complicated.

If I use parametrisation, then I get

double integral of [(r^2)cos^2(t)-(r^2)sin^2(t)+2) rdrdt

what are the bounds though?

t is between 0 and 2pi I'm pretty sure, but what about r?

It seems difficult since x^2+y^2 is greater than or equal to 2. This means that r^2 is greater than or equal to 2. Thus, it seems sqrt(2) is a lower bound, but what would the upper bound be?

Does this make any sense?

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# Help on easy integration

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