# solve a system of integral equations with matlab

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ALBORZ NAJAFI on 15 Jul 2021
Commented: ALBORZ NAJAFI on 21 Jul 2021
Hi every body
I wrote the attached code to solve the integral equations written in the image.But I have a problem with matlab error
Can anyone help?
function S = Integralsystem(x,va,vb,t,xa)
x=1+int(va,t,0,t)+int(vb,t,0,t)
va=1.2*int((4/x^2-0.5/xa^2),t,0,t)
vb=(4/3)*int((3/x^2+.5/(x+xa)^2),t,0,t)
xa=70-int(va,t,0,t)
s=fsolve

Torsten on 17 Jul 2021
If you differentiate all your equations with respect to t, you get a system of differential equations that can be solved by standard Matlab software (like ode45, ode15s etc.).
ALBORZ NAJAFI on 21 Jul 2021
thanks a lot
I solved the problem and wrote the code

Jayant Gangwar on 15 Jul 2021
You need to pass the complete system of non linear equations to fsolve as input argument along with start conditions, just calling fsolve will not process anything. For information on how to pass a system of equations to fsolve please go through it's documentation, I've attached the same below
Also you can take a look at the following ML answer