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Solving nonlinear equations self consistently

Posted 5 months ago
3 Replies
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Hello everyone,

I am trying to solve two nonlinear equations for variables y and z self consistently but stuck with an error while executing FindRoot which is given in attached mathematica file.

I would appreciate any help for resolving the issue or suggestions to solve the problem in a different way.

Thank you

3 Replies
Posted 5 months ago

Hi Tiku,

This looks wrong

val1 = gn /. solvegn1 // Real // Positive

What are you trying to accomplish with // Real // Positive? Check the documentation for those symbols.

Posted 5 months ago

Thank you for the reply. I realized my mistake, actually it should be val1 = gn /. solvegn1[[1]] for reading first root out of four roots.

Solving first equation for each n gives me four roots of gn and I was trying to choose only real positive ones for each n (let's say n=0 and four gn and trying to choose for only real positive values) so I used Real//Positive.

I will forget nature of the roots and If I take into account all four roots then plugging those in last two equations gives me four y and four z values but journal calculation shows only one positive y and z values so I was trying to choose only real positive gn value.

Could you please solve for y and z values for each gn?

In short I am trying to solve for y and z values from last two equations.

Thank you

Posted 5 months ago

I see and thank you for awaking me. Below pdf shows the required equations detailing the process. Equation 3 4 and 5 has to be solved numerically to get y and z values.

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