# Is there a way to extract my 3 transfer function in matlab given these equations.

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Jorje German on 3 Sep 2020
Commented: Sam Chak on 10 Sep 2020
I have these 3 equations
X1(s)*[m1*s^2 + c1*s+(k01+k12)] = F(s) + k12*X2(s)
X2(s)*[m2*s^2 + c2*s +(k12+k23)] = k12*X1(s)+k23*X3(s)
X3(s) [m3*s^2 + c3*s +(k23+k34)] = k23*X2(s)
and I am wondering if there is a possibility to be able to extract my 3 transfer functions, X1(s)/F(s), X2(s)/F(s), and X3(s)/F(s).
Ive really havent explore this part of Matlab and am interested to know if it is possible. I ask because currently I am doing it by hand and setting the left side S polynomial to be P1, P2, and P3 respectively.
but it is alot of algabra and I fear I will make a simple arithmetic mistake and ruin the whole thing.
Can this be done.
##### 2 CommentsShowHide 1 older comment
Jorje German on 3 Sep 2020
Interesting concept. I just showed my wife and she said, this is why you are still a student. I will try this method and play around in Matlab. Thank you. You have given me a direction to go to.

Sam Chak on 3 Sep 2020
The transfer functions for your case in given in the first column of the matrix. You can use the functions in Symbolic Math toolbox to simplify the rational expressions. Hope my answer helps.
Sam Chak on 10 Sep 2020
https://www.mathworks.com/products/symbolic.html

R2020a

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