Solution of wave equation, 2nd partial derivatives of time/position

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The discussion focuses on the solution of the wave equation expressed through the function f(z,t) and its second partial derivatives with respect to time and position. It highlights the relationship between these derivatives, which differ by a factor of v², and questions whether this represents a hyperbolic partial differential equation. The conversation references Alembert's principle that one-dimensional waves can be expressed as the sum of right and left-moving functions. Additionally, it mentions deriving wave speed from Maxwell's equations, specifically referencing the Weber/Kohrausch ratio. The analysis emphasizes the mathematical intricacies of wave behavior and its foundational principles in physics.
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f(z,t)=\frac{A}{b(z-vt)^{2}+1}...

\frac{\partial^{2} f(z,t)v^{2} }{\partial z^2}=\frac{-2Abv^{2}}{[b(z-vt)^{2}+1]^{2}}+\frac{8Ab^{2}v^{2}(z-vt)^{2}}{[b(z-vt)+1]^{3}}=\frac{\partial^2 f}{\partial t^2}
\frac{-2Abv^{2}}{[b(z-vt)^{2}+1]^{2}}+\frac{8Ab^{2}v^{2}(z-vt)^{2}}{[b(z-vt)+1]^{3}}

this is a solution of the wave equation, but it can be written with the Laplacian. is this also a hyperbolic partial differential equation. Alembert derived the solution that 1D waves are the addition of right and left moving functions

what is the meaning of the 2nd partial derivatives in respect to time and position which differ by v^2? (I wrote this on online Latex editor, the differentiation is in the attachment)
thanks very much!
 

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so you can derive the speed c from the Maxwell equations which for an electromagnetic wave is the Weber/Kohrausch ratio 1/(epsilono*muo)^(1/2)...
 
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