### Author Topic: problem 3  (Read 35643 times)

#### Aida Razi

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##### Re: problem 3
« Reply #15 on: October 13, 2012, 09:25:45 PM »
Question 3 part a: p has to be= ((y-x+2kÎ±t) / (âˆš 2kt)) instead of ((y-x+2kÎ±t) / (âˆš 4kt)) in Peishan's solution.

#### Peishan Wang

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##### Re: problem 3
« Reply #16 on: October 14, 2012, 01:56:36 AM »
I think it doesn't matter. If you use the error function (the first attachment) provided by our professor, then you let p = ((y-x+2kÎ±t) / (âˆš 2kt)). If you use the other form (the second attachment) which is used in the textbook, then you let p = ((y-x+2kÎ±t) / (âˆš 4kt)).

And in another post, http://forum.math.toronto.edu/index.php?topic=49.0 Julong has shown that these two forms are actually equivalent.

Professor can you provide some feedback to the posted solutions? It seems that you ignored this post completely. Thanks.
« Last Edit: October 14, 2012, 02:02:23 AM by Peishan Wang »

#### Victor Ivrii

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##### Re: problem 3
« Reply #17 on: October 14, 2012, 04:22:42 AM »
I think it doesn't matter. If you use the error function (the first attachment) provided by our professor, then you let p = ((y-x+2kÎ±t) / (âˆš 2kt)). If you use the other form (the second attachment) which is used in the textbook, then you let p = ((y-x+2kÎ±t) / (âˆš 4kt)).

And in another post, http://forum.math.toronto.edu/index.php?topic=49.0 Julong has shown that these two forms are actually equivalent.

Professor can you provide some feedback to the posted solutions? It seems that you ignored this post completely. Thanks.

You are correct.

PS I am not on 24/7 shift

#### Aida Razi

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##### Re: problem 3
« Reply #18 on: December 18, 2012, 12:45:51 PM »
Solution to question3 part b is attached!

#### Fanxun Zeng

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##### Re: problem 3
« Reply #19 on: December 18, 2012, 07:20:40 PM »
Thanks Aida for posting Part b in December. As there is still NO solution posted for Part d yet, I spent 1 hour to write part d and post attached same 2 images, first by camera, second by scan.

Thanks professor. Here I used error function in the textbook, instead of that given in the homework, but yes they are same. In part d, I got limit u(x,t)=1 for Neumann condition.
« Last Edit: December 18, 2012, 07:25:23 PM by Peter Zeng »