how do you use the change of variable:(adsbygoogle = window.adsbygoogle || []).push({});

[itex]\xi[/itex] = x - ct

on the PDE

u_{t}+ c u_{x}= 0

where u(t,x) = v(t,x-ct) = v(t,[itex]\xi[/itex])

to get

v_{t}= 0

I am trying to follow the steps of Peter J. Olver in this document http://www.math.umn.edu/~olver/pd_/lnw.pdf [Broken] starting on pg 4 but get stuck here...i think i am missing an important calculus concept but cannot figure out what. He says to use the chain rule but i cannot figure out how that helps.

Any help GREATLY appreciated

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# Transport Equation

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