a(1)=1;
t=2;
h(1)=0.02;
y(1)=f2(a);
e=10^(-4);
while(k>0)
   a(k+1)=a(k)+h(k);
   y(k+1)=f2(a(k+1));
   if(y(k+1)<y(k))
      h(k+1)=t*h(k);
      af=a(k);
      a(k)=a(k+1);
      k=k+1;
  elseif
      if(k==1)
          h(k)=-h(k);
          a(k)=a(k+1);
      end
   else
      break;
   end
end
   a=min(af,a(k+1));
   b=max(af,a(k+1));