Transforming to a Normal Form (PDE)

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Homework Statement
Find the type, transform to normal form and solve. Show your work in detail: Uxx+2Uxy+Uyy=0
Relevant Equations
Hyperbolic- AC-B^2<0
Parabolic- AC-B^2=0
Elliptic- AC-B^2>0
I don't know how to solve for u(x,y) from where I left of after 5.

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Shouldn't you be getting: ##u_{ww}=0##, i.e. ##u(w,v)=Aw+B(v)## where ##B(v)## is a function of ##v## and ##A## is a constant?
 
MathematicalPhysicist said:
Shouldn't you be getting: ##u_{ww}=0##, i.e. ##u(w,v)=Aw+B(v)## where ##B(v)## is a function of ##v## and ##A## is a constant?

The indefinite integral of 0 with respect to w is an arbitrary function of v, not an arbitrary ocnstant.
 
pasmith said:
The indefinite integral of 0 with respect to w is an arbitrary function of v, not an arbitrary ocnstant.
yes correct then A should be A(v).
 
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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