(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

my non linear pde is

du/dt = d/dx [3u^{2}- d^{2}u/dx^{2}]

The question says to let u(x,t) = f(x-ct)

Where the function f tends to 0, f' tends to 0 and f'' tends to 0 but the (x-ct) tends to positive or negative infinity.

2. Relevant equations

i thought the solution was to find du/dt du/dx d^{2}u/dt^{2}and d^{2}u/dx^{2}

Which gave me in order as above, -cf' , f' , c^{2}f'' , f''

3. The attempt at a solution

But when i substitute these into the pde i get -cf' = d/dx[3f^{2}- f"] which im not sure actually helps

Could someone please tell me if i am using the correct method or if i have done it completely wrong

Thank you

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# Homework Help: Non linear pde need to change it to an ode

Can you offer guidance or do you also need help?

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