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jbusc
Oct25-06, 06:34 PM
Hi,

when solving PDE's of the form au_{xx} + 2bu_{xy} + cu_{yy} = 0 where ac - b^2 = 0 (i.e., parabolic)

is the solution always of the form:

u = xf_1 (\phi) + f_2(\phi)

where

\phi is the solution to the characteristic equation a(y')^2 -2by' + c = 0

If not, is there a general form in this sense? (Related to the heat equation in the same way that d'Alembert's form relates to the wave equation)

Thanks, any help at all please is welcome.