### Author Topic: Difference between what we talk about in Chapter 3 & 4  (Read 1380 times)

#### ziyao hu

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##### Difference between what we talk about in Chapter 3 & 4
« on: October 19, 2016, 10:54:31 AM »
I'm wondering why in Chapter 4, we need 2 boundary conditions, if we can solve the problem with only 1 b.c. just as the problem 5 in Assignment 5?
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#### Victor Ivrii

Now, we need two  initial conditions (as $t=0$) for wave equation, and one for heat equation because the former has an order 2 with respect to $t$, and the latter has order $1$. This was explained in details during the lecture.