Solving coupled Differential equations

I tried to solve following diff. eq. using 'dsolve' but (maybe) it's impossible.

So please help me how to solve following eq.s using matlab!!!!!

syms s1 s2 s3 g1 g2 g3 p1 p2 p3 t
h = 1; b = 2; e = exp(1); v = 1;
diffqp1 = 'Dp1 = h*b*s1*(g1-p3)-(e/v)*p1'
diffqp2 = 'Dp2 = h*b*s1*(g1-p3)-(e/v)*p2'
diffqp3 = 'Dp3 = h*b*s1*(g1-p3)-(e/v)*p3'

diffqs1 = 'Ds1 = -h*b*s1*(g1-p3)-(e/v)*s1'
diffqs2 = 'Ds2 = -h*b*s1*(g1-p3)-(e/v)*s2'
diffqs3 = 'Ds3 = -h*b*s1*(g1-p3)-(e/v)*s3'

[Nicolas Schmit]

Please provide the error message.

https://www.mathworks.com/matlabcentral/answers/6200-tutorial-how-to-ask-a-question-on-answers-and-get-a-fast-answer

Also, do note use quotations when defining diffqp1,diffqp2, etc. Define all symbolic variables first, then create a symbolic expression from these variables.

[Walter Roberson]

• Are your g1 g2 g3 functions or constants?
• What boundary conditions are there?
• you never use g2 or g3 but use g1 repeatedly

Presuming that g1 is a constant and not a function, then current syntax would look like

syms s1(t) s2(t) s3(t) g1 g2 g3 p1(t) p2(t) p3(t)
h = 1; b = 2; e = exp(1); v = 1;

Dp1 = diff(p1); Dp2 = diff(p2); Dp3 = diff(p3);
Ds1 = diff(s1); Ds2 = diff(s2); Ds3 = diff(s3);

diffqp1 = Dp1 == h*b*s1*(g1-p3)-(e/v)*p1;
diffqp2 = Dp2 == h*b*s1*(g1-p3)-(e/v)*p2;
diffqp3 = Dp3 == h*b*s1*(g1-p3)-(e/v)*p3;

diffqs1 = Ds1 == -h*b*s1*(g1-p3)-(e/v)*s1;
diffqs2 = Ds2 == -h*b*s1*(g1-p3)-(e/v)*s2;
diffqs3 = Ds3 == -h*b*s1*(g1-p3)-(e/v)*s3;

eqns = [diffqp1, diffqp2, diffqp3, diffqs1, diffqs2, diffqs3];

sol = dsolve(eqns);

[JaeSung Choi]

Really thanks for your comment. I'm sorry for that I forgot some constants.