Mathematica Need help to solve simultaneous equation in Mathematica

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The discussion revolves around solving simultaneous equations using Mathematica. The user initially faces difficulties determining if their system has a solution. After applying CoefficientArrays to convert the equations into a matrix format, they find that the determinant of the matrix is non-zero, suggesting a solution exists. However, the presence of many degenerate singular values indicates that the singular value decomposition may not be unique, raising questions about the uniqueness of the solution. The user also inquires about the small imaginary numbers in their results, which are confirmed to be correct, and considers whether to retain them. Additionally, the user expresses a lack of understanding of certain Mathematica functions like CoefficientArrays and SingularValueList, indicating they are new to the software and seeking clarity on these concepts to resolve their issues.
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Hi everyone, please help me to solve my difficulties with regard to simultaneous equations using Mathematica.

Thanks for any response.
 

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It looks like your system of equations does not have a solution. You might try using CoefficientArrays to turn it into a matrix problem.

EDIT: Hmm, something seems strange. I turned this into a matrix problem by

{b, m} = CoefficientArrays[eqn, vars]

And it turns out that Det[m] gives a non-zero result, so there should be a solution. And, in fact, Inverse[m].b gives a good array of coefficients. However, SingularValueList[m] shows that there are a lot of degenerate singular values, so the singular value decomposition is not unique. I don't know if that means that maybe there is not a unique solution.

Are the small imaginary numbers correct, or can we Chop those off?
 
Last edited:
Thanks for reply..

Actually, I have chopped off the real values of U1, U2, V1 and V2, because they are too lenghty, and I could not fit in the attachement file. Perhaps, if I use the full expressions of U1, U2, V1 and V2, it would give me the good response. I don't know if I could send you the complete file.

Yes the imaginary parts are very small, they are correct. I think I just better keep them throughout.

By the way, I have checked from the manual and books, I really don't have idea how the CoefficientArrays and SingularValueList[m] works as Iam relatively new to Mathematica. For now, Iam trying to figure out what those terms mean and help me to solve my problems.

Thanks anyway.
 

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