Hi. I am taking a PDE class and struggling a little. The professor gave us this problem to practice:(adsbygoogle = window.adsbygoogle || []).push({});

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 ${(x,0)}$

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!

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

Can you offer guidance or do you also need help?

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