# Warning: Solution does not exist because the system is inconsistent.

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Max Rothstein on 11 Feb 2021
Commented: Max Rothstein on 11 Feb 2021
I'm not sure whats wrong with my code here, but it wont solve the system of equations. Maybe I'm missing something.
w1 = 0.05*pi;
w2 = 0.1*pi;
w3 = 0.2*pi;
syms b1 b2 b3
Bw1 = 2*b1*cos(2*w1)+2*b2*cos(2*w1)+b3 == 0;
Bw2 = 2*b1*cos(2*w2)+2*b2*cos(2*w2)+b3 == 1;
Bw3 = 2*b1*cos(2*w3)+2*b2*cos(2*w3)+b3 == 0;
[A,B] = equationsToMatrix([Bw1, Bw2, Bw3], [b1, b2, b3]);
X = linsolve(A,B);
Daniel Pollard on 11 Feb 2021
I've not used the symbolic toolbox, but I'd have a guess that if it says "the system is inconistent" and won't solve your system of equations, I'd have a guess that perhaps your equations aren't consistent with each other.

Bjorn Gustavsson on 11 Feb 2021
Edited: Bjorn Gustavsson on 11 Feb 2021
Have a look at the equations. If you rewrite them you will get:
Bw1 = ( b1 + b2 ) * 2*cos(2*w1) + b3 == 0;
Bw2 = ( b1 + b2 ) * 2*cos(2*w2) + b3 == 1;
Bw3 = ( b1 + b2 ) * 2*cos(2*w3) + b3 == 0;
That will explicitly show you that you can only solve for b3 and the sum of b2 and b1.
HTH
Max Rothstein on 11 Feb 2021
Thank you, that makes sense.

R2020a

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