solve a system of differential equations

System is like this:

A'=-A*exp(k1/C)

B'=m1*A*exp(k1/C)+m2*B*exp(k2/C)

C'=m3*A*exp(k1/C)+m3*B*exp(k2/C)

Where A=A(t), B=B(t), C=C(t) and A'=dA/dt and 3 initial conditions exist.

m1 m2 m3 k1 k2 ...are constants

Please tell me how to solve it,I already tried dsolve but there is no explicit solution

A link to a tutorial would be useful too.

Thanks

And what this set of differential equations is called like ODE OR PDE?

[vahid army]

Did anyone at least read it?

[Titus Edelhofer]

Yes, I did ;-).

Answer 1

[Titus Edelhofer]

Hi Vahid,

did you already try to solve it numerically? It should be straightforward to solve using ode45. You function that you pass to ode45 should look something like

function dy = fun(t, x, m1, m2, k1, k2, C)
A = x(1);
B = x(2);
C = x(3);
dA = -A*exp(k1/C);
% etc
dy = [dA; dB; dC];

and then you call ode45 with

[t,y] = ode45(@(t,x) fun(t, x, m1, m2, k1, k2, C), ...)

Titus

[vahid army]

Thanks I'll study about ode45