## Integrating f^2 over a square?

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### Integrating f^2 over a square?

Hi guys,

This is gonna sound really stupid, but I was wondering how you integrate a function g = ( f(x,y) )^2 over a square region.

Fundamental theorem of calculus says that, if F is the antiderivative of f, integrating f(x,y) over the region = (FA)e - (FA)w
where (FA)e refers to the value of F along the eastern side of the square multiplied by A, the length of the east side of the square.

What would the answer be for integrating g(x,y) in terms of F?

Thank you!
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mph_Ragnarok
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### Re: Integrating f^2 over a square?

Sounds like a job for Convolution...
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### Re: Integrating f^2 over a square?

Game_boy
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### Re: Integrating f^2 over a square?

Game_boy wrote:You're more likely to get an answer from other people doing your course or your teacher/supervisor. They can also explain it instead of just stating an answer.

This isn't homework, thanks for assuming.
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mph_Ragnarok
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### Re: Integrating f^2 over a square?

mph_Ragnarok wrote:
Game_boy wrote:You're more likely to get an answer from other people doing your course or your teacher/supervisor. They can also explain it instead of just stating an answer.

This isn't homework, thanks for assuming.

And this or this or this or this isn't homework either? You're at a university and you know no one that might be able to help with this?
Last edited by Game_boy on Thu Mar 15, 2012 10:52 am, edited 1 time in total.
Game_boy
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### Re: Integrating f^2 over a square?

Game_boy wrote:And this or this or this or this isn't homework either? You're at a university and you know no one that might be able to help with this?

Some of your links with goofy URLs got me logged out of TR. Probably the trweb7 link or the one with the IP address.
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### Re: Integrating f^2 over a square?

You're right, it does sound really stupid.
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