[Math] Wave Equation – like 4th Order PDE

partial differential equations

How does one solve a fourth-order PDE of the form $\frac{\partial^4y}{\partial x^4}=c^2\frac{\partial^2y}{\partial t^2}$? It looks like a one dimensional wave equation, but I'm unfortunately very bad at PDEs.

Best Answer

You do almost the same thing as people explained in your other question. Unfortunately, you can only factor the operator into

$$ \left(\frac{\partial^2}{\partial x^2} - c\frac{\partial}{\partial t}\right) \left(\frac{\partial^2}{\partial x^2} + c\frac{\partial}{\partial t}\right)y = 0. $$

Then you have to solve a heat-equation like equation.

If your domain is finite, you should try separation of variables.

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