Solving for u: Struggling with a 2D Homework Problem

[dirk_mec1]

Homework Statement

The Attempt at a Solution

I don't know how to choose u. I presume we look in 2D; I thought u should look something like:

$$u = \left[ \begin{array}{c} \psi \\ \psi \end{array} \right]$$

and $$c= \phi$$ but that isn't correct.

 

[Dick]

How about picking two vector fields? Pick u=(psi,0) for the first part and u=(0,psi) for the second part.

 

[dirk_mec1]

How about picking two vector fields? Pick u=(psi,0) for the first part and u=(0,psi) for the second part.

Yes of course, thanks Dick!