How to solve coupled ODE problem

I'm trying to solve system of coupled ODE's.

assume that =Ydot, =Y, r=4.

If I have five equations which are

Ydot1 =

Ydot2 =

Ydot3 =

Ydot4 =

Ydot5 =

How can I solve these ODE equations with its result as a graph.

Or at least, how can I solve coupled ODE with Ydot on both sides. Like,

Answer 1

[David Goodmanson]

Hi seoyeon,

It's easy enough to solve for Ydot4 in the fourth equation. Then if you put that up front in the code, you can plug the result into what is now the first equation to obtain

Ydot4 = 8*Y3*Y4 / (1+Y1);
Ydot1 = r*Y1^2 + 6*Y1*Y3 + Ydot4;

The (1+Y1) in the denominator may cause some problems, but that's what the equations are saying.