
clear
f=5.11;
 m=400.3;
 a=m*f/(f-1);b=m-a;
 sigma=102.66;
 lamda=m*f/((f-1)*sigma);
 d=lamda^2;
x=0:100:800
si=5;
for k=1:length(x),
v=si^2;
w=v^2;
g=a/d;
h(k)=x(k)-b;
c(1)=2*g*w;
c(2)=-v*(v+4*h(k)*g);
c(3)=2*h(k)*(v+g*h(k));
c(4)=a^2-h(k)^2;
roots(c)
end