PDE separation of variable problem

JamesGoh
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Homework Statement



Using the method of separation of variables, obtain a solution of the following PDE subject to
the given conditions

\frac{du}{dx}+y\frac{du}{dy}=(2x+y)u

u(x,1)=5e^{x^{2}-x}


Homework Equations





The Attempt at a Solution



See my attached working

the answer is u(x,y)=5ye^{y-1+x^{2}-x}

Im not sure if I am getting anywhere near close in my working out. Have double checked the arithemetic and everything seems fine so far
 

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hi guys

an update on the problem. I managed to solve it.

The issue was that I didn't consider the arbirtrary integration constant, C, when doing the integral of the Y term.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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