%ex1 10.12.08

clear all; 
clc;
X=1:0.01:6;
% Y=X.^2-5;
myfunc=@(x)x.^2-5;
Y=myfunc(X);

a=1;
b=6;


for n=1:30
    disp(['Iteration : ' num2str(n)])
    disp(sprintf('a = %.4f b = %.4f',[a b]))
    c = a + (b-a)/2;
    if myfunc(a)*myfunc(c)<0        
        b = c;
    else
        a = c;
    end
    
    hold on
    plot(b,myfunc(b),'--rs','Linewidth',2,'MarkerSize',10,'MarkerFaceColor','g');
    hold on
    plot(a,myfunc(a),'--gs','Linewidth',2,'MarkerSize',10,'MarkerFaceColor','r');
    
end
plot(X,Y,X,0,'-r','Linewidth',2);
grid
disp('function is equal 0 in interval from :');a
disp('to :');b