how to plot graph for SIR epidemic model

my SIR epidemic model is

dS/dt= beta-lembda*I*S-u*S;
dI/dt=lembda*I*S-u*I-gamma*R;
dR/dt=gamma*R-u*R;
t=0:1:100;
gamma=.10;
lembda=.5;
u=.2;
S=50;I=20;R=30;

[KSSV]

What have you attempted?

[Ruksana Shaikh]

function x = sir(t, x)

x(1)=0:50:100;

x(2)=0:10:50;

x(3)=0:10:70;

beta = .5;

delta = .3;

x(1) = -beta * x(1) * x(2);

x(2) = beta * x(1) * x(2) - delta * x(2);

x(3) = delta * x(2);

plot (t,x(1),t,x(2),t,x(3))

end

[Ruksana Shaikh]

please guide me

[Ruksana Shaikh]

function x = sir(t, x)

x(1)=0:50:100;

x(2)=0:10:50;

x(3)=0:10:70;

beta = .5;

delta = .3;

x(1) = -beta * x(1) * x(2);

x(2) = beta * x(1) * x(2) - delta * x(2);

x(3) = delta * x(2);

plot (t,x(1),t,x(2),t,x(3))

end

Answer 1

[Sunday Aloke]

Please I need help on the matrix in the document attached. My MATLAB has no symbolic toolbox as in to run, can someone help me and get the determinants of the matrices l?

Thanks