tic

k=0;

% b=a-f(a)/Df(a); k=k+1;

itmax=15;

k
[b abs(b-a)]
fa=f(a);

while abs(b-a)>tol*max(abs(b),1.0)
     if k+1>itmax
       break
     end 
     fb=f(b);
     x = b + (b-a)/(fa/fb-1);
     k=k+1
     a=b;
     fa=fb;
     b=x;
     c(k,1)=b;
     [b abs(b-a)]
end  

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