# Solution to a simple equation

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RAN am 17 Mai 2021
Beantwortet: Stephan am 17 Mai 2021
Hello all,
I am trying to find a solution to a simple problem, the solution exist but I am unable to get it in the correct format
clear all; close all;
syms R L C omega real
eqn=1 - 2*C*L*omega^2 + C^2*R^2*omega^2 + C^2*L^2*omega^4 == 0
R_soln=solve(eqn,R)
I expect a solution for 'R' by moving all the terms to RHS, and in terms of omega, C, L
However I get the following answer
R_soln =
Empty sym: 0-by-1
This has happened many times before, I am trying to understand why solve cannot give me a solution.
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RAN am 17 Mai 2021
I got the solution to the problem mentioned, but I cant get it in the format I want.
Since I have explicitly defined the variables as real, Matlab tries to find a real solution which does not exist.
The following works:
clear all; close all;
syms R L C omega
eqn=1 - 2*C*L*omega^2 + C^2*R^2*omega^2 + C^2*L^2*omega^4 == 0
R_soln=solve(eqn,R)
However I just want to rearrange the equation to get all the terms ot RHS except for R.
Any idea how to do it?

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### Akzeptierte Antwort

Stephan am 17 Mai 2021
clear all; close all;
syms R L C omega
eqn=1 - 2*C*L*omega^2 + C^2*R^2*omega^2 + C^2*L^2*omega^4 == 0
eqn = C^2*L^2*omega^4 + C^2*R^2*omega^2 - 2*C*L*omega^2 + 1 == 0
R_soln=isolate(eqn,R)
R_soln = R == ((C*L*omega^2 - 1)*1i)/(C*omega)
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