I'm trying to define a simbolic variable like ¨ syms x ¨. I used to do it but now It doesn't work..

Example of the code:

syms I1 I2 z1 z2 z3 z4 kt I3 I4 M K

M=[I1+I2*(z1^2/z2^2) 0;0 I3*z4^2/z3^2+I4]

K=[(z1^2/z2^2)*kt -(z1*z4)*kt/(z2*z3);-(z1*z4)*kt/(z2*z3) (z4^2/z3^2)*kt]

D=inv(M)*K

[V,D]=eig(D)

M=[16 6;6 4]

K=[88.29 0;0 29.42]

Answer 1

[Star Strider]

Run these lines from your Command Window or a script:

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Answer 2

[Erivelton Gualter]

Maybe you do not have the Symbolica Package installed or do not have license. Run the following comand on command windows:

ver

And check for the following in bold:

Symbolic Math Toolbox                                 Version X.X         (R20XX)

Also check if you have a license for this package:

https://www.mathworks.com/licensecenter

*By the way, your code is fine.

[Xavi Alm]

I have the licence..

[Xavi Alm]

I have this message error