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Lucas
Posts:
1
Registered:
9/22/11


Solving u_y + a(x,y) u_x = 0 for function a(x,y) that yields no solution
Posted:
Sep 22, 2011 7:08 PM


Hi. I am taking a PDE class and struggling a little. The professor gave us this problem to practice:
_____________________________________________________
Find a function a = a(x,y) continuous such that for the equation $u_y + a(x,y) u_x = 0 $ there does not exist a solution in all of $R^2$ for any nonconstant initial value defined on the hyperplane ${(x,0)}$ _____________________________________________________
I thought that in order to find such a function I needed to make the hyperplane characteristic at all points, but that got me nowhere. Please help me find a direction. Any help would be much appreciated!
Thanks in advance!



