摘要
In this paper, we prove that the chord method and the modified chord method are also convergent to the solution x<sup>?</sup> of F（x）=0 if the dimension of the null space of F’(x<sup>?</sup>) is】1.
In this paper, we prove that the chord method and the modified chord method are also convergent to the solution x°of F(x)=0 if the dimension of the null space of F' (x°) is>l.
