Second order Eigenvectors

[FerMedina]

Hi, I'm trying to describe the Stroh formalism for anisotropic plates and I can't solve the eigenvectors for an eq. of the type " (A + B*l + C*l^2) * V = 0 ", where A, B and C are 3x3 matrix. I find solutions for l via solve and float, or polyroots if I don't use units with the matrix. But I can't find the associated V. If use find i get no result. If use minerr the results vary with the initial guess value.
I could definitely use your help with this.

I'm attaching a short version of the worksheet.
Thanks a lot.

 

[Spiry]

The ecuation you are have infinetly solutions and you can work with some parameters I modify you can see my idea .the result for simply is dispalyed but cant be save you will see