PHYSICS · Multi-part · Fermi University Physics · Mathematical Methods for Physics · Partial differential equations and boundary-value problems · Partial differential equations and boundary-value problems
Conditions of Validity, Ch The three equations, their characteristics and what makes a problem well posed
Problem
A field u(x,y) satisfies uxx+xuyy=0.
((a)) Find the regions of the (x,y)-plane in which the equation is elliptic and in which it is hyperbolic.
((b)) For x<0, derive the equation of the characteristic curves.