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# 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);
##### 1 CommentShowHide None
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.

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### Accepted Answer

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
##### 1 CommentShowHide None
Max Rothstein on 11 Feb 2021
Thank you, that makes sense.

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