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Topic: Solving u_y + a(x,y) u_x = 0 for function a(x,y) that yields no solution
Replies: 0

 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:

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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 non-constant initial value defined on the hyperplane \${(x,0)}\$
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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!