### Author Topic: Last Year HW:5.4.12  (Read 13218 times)

#### Aida Razi

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##### Last Year HW:5.4.12
« on: November 11, 2012, 10:33:08 PM »
I am just wondering in this question when P.T. wrote Parseval's equality, it shouldn't contain "integral |sin(nÏ€x/l)|^2"; Right?

#### Victor Ivrii

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##### Re: Last Year HW:5.4.12
« Reply #1 on: November 12, 2012, 04:58:43 AM »
Aida, please next time provide a link, like this one
http://weyl.math.toronto.edu:8888/APM346-2011F-wiki/index.php/Home_Assignment_8#5.4.12.

I am just wondering in this question when P.T. wrote Parseval's equality, it shouldn't contain "integral |sin(nÏ€x/l)|^2"; Right?

Yes, except $\int_0^l |sin(nÏ€x/l)|^2\,dx =l/2$, so you don't need this integral. Ditto for 5.4.13, 5.4.15.

And who is P.T.?

#### Aida Razi

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##### Re: Last Year HW:5.4.12
« Reply #2 on: November 12, 2012, 11:57:41 AM »
Aida, please next time provide a link, like this one
http://weyl.math.toronto.edu:8888/APM346-2011F-wiki/index.php/Home_Assignment_8#5.4.12.

I am just wondering in this question when P.T. wrote Parseval's equality, it shouldn't contain "integral |sin(nÏ€x/l)|^2"; Right?

Yes, except $\int_0^l |sin(nÏ€x/l)|^2\,dx =l/2$, so you don't need this integral. Ditto for 5.4.13, 5.4.15.

And who is P.T.?

"Paul Tan" Last year student.

#### Victor Ivrii

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##### Re: Last Year HW:5.4.12
« Reply #3 on: November 12, 2012, 01:59:45 PM »

Yes, except $\int_0^l |sin(nÏ€x/l)|^2\,dx =l/2$, so you don't need this integral. Ditto for 5.4.13, 5.4.15.

And who is P.T.?

"Paul Tan" Last year student.
[/quote]

Shame on me--I forgot--he was the best online help!