# Linear partial differnetial equations (PDE's)

by Niles
Tags: differnetial, equations, linear, partial
 P: 1,818 1. The problem statement, all variables and given/known data Please take a look at the example at the bottom (at eq. 18:18, at page 619): http://books.google.dk/books?id=9p6s...l=da#PPA619,M1 Q1: In case (ii), why do they add g(x^2+y^2)? Q2: Why do they not add it in case (i)? Q3: In case (ii), if I chose f(p) = p + 1 instead of f(p) = 2p, then the solution would be u(x,y) = 1+ x^2 +y^2 + g(x^2 + y^2), right? I hope you can help me; I find this really hard to understand, and I've spent hours trying to find out, but I find that the book is poorly written. They don't emphasize the important things at all, and the reader is left behind with so many questions. Thanks in advance.
 P: 1,818 The difference between (ii) and (i) is that in (i) it is a function, but in (ii) it is a single point. Although I am not sure about this?
 P: 1,818 Can you guys give me a hint? I still can't see the system in it.
HW Helper