function x = Ecuacion_Segundo_Orden(xini, h, N, A)
   D = zeros(N, N);
   b = zeros(N, 1);
   
   for k=1:N
       D(k,k) = A(1);
       if k>1
           D(k,k-1) = A(2);
       end;
       if k>2
           D(k,k-2) = A(3);
       end
       
       b(k) = A(4);
       if k == 1
           b(k) = b(k) - A(2)*xini(1) - A(3)*xini(2);
       end
       if k == 2
           b(k) = b(k) - A(3)*xini(1) ;
       end
   end;
   
   x = inv(D)*b;
end