Solution of 2 Equations with 3 Variables

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Discussion Overview

The discussion revolves around solving two equations with three variables, specifically focusing on the variables Es, Einf, and T. The context includes mathematical reasoning and problem-solving related to these equations.

Discussion Character

  • Mathematical reasoning
  • Homework-related

Main Points Raised

  • One participant initially posted equations in a file, which was found to be blank, leading to a discussion about file sharing and accessibility.
  • Another participant provided the correct equations, which are related to the permittivity in a physical context.
  • It was noted that with only two equations and three unknowns, it is not possible to solve for all three variables; instead, two can be expressed in terms of the third.
  • A method was suggested to eliminate fractions by manipulating the equations, leading to a potential expression for one variable in terms of another.
  • A request was made for a detailed solution to the problem, indicating a need for further clarification and assistance in mathematical processes.

Areas of Agreement / Disagreement

Participants generally agree that the equations cannot be solved for all three variables simultaneously, but multiple approaches to express two variables in terms of the third are discussed. The discussion remains unresolved regarding the detailed solution process.

Contextual Notes

Participants have not fully explored the implications of the equations or the specific values of the known variables, which may affect the solution process.

Who May Find This Useful

Readers interested in mathematical problem-solving, particularly in the context of equations with multiple variables, may find this discussion relevant.

m_niz
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Hello there,

I have got the following equations, please see the attached file.



Have to find Es, Einf and T. others are known. How to do that? Thanks.
 

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You should understand that most people will not open WORD files for fear of viruses. Since I have very strong virus protection, I took the chance. Of course, it took a while to load since it had to go through all the virus tests.

In any case, I am now embarassed that I did since I should have seen, from the title "New Microsoft Word Document" that the document is blank!
 
Yeah Halls is right, it's completely blank.
 
Very Sorry, I have loaded the correct file now! actually its a bit tricky to write these equations so I just attached the file. Thanks
 
The two equations, then, are
[tex]\epsilon'= \epsilon_\infty+ \frac{\epsilon_s- \epsilon_\infty}{1+ (\omega \tau)^2}[/tex]
and
[tex]\epsilon"= \frac{(\epsilon_s- \epsilon_\infty)\omega\tau}{1+ (\omega \tau)^2}[/tex]}

Of course, since there are only two equations in 3 unknown values, you cannot solve for all three. What you could do is solve for two of them in terms of the third.

You might, for example, multiply the first equation by [itex]\omega\tau[/itex], so that the two fractions are the same, and then subtract one equation from the other, eliminating the fractions:
[tex]\epsilon'- \epsilon"= \epsilon_\infty (\omega\tau)[/tex]
Then
[tex]\epsilon_\infty= \frac{\epsilon'-\epsilon"}{\omega\tau}[/tex]
so you have solved for [itex]\epsilon_\infty[/itex] in terms of [itex]\tau[/itex].

Replace [itex]\epsilon_\infty[/itex] by that in either of the two equations, and you can then also solve for [itex]\epsilon_\infty[/itex] in terms of [itex]\tau[/itex].
 
Thanks Hall! Can you write me a detailed solution. I am not very good in maths.
 

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