History of Hindu Mathematics: A Source Book v1.c8.s10.22

v1.c8.s10.22

There is thus no doubt as to the Hindu origin of the check of nines. Before Âryabhaṭa II, it was probably used to test multiplication and division only. It was perhaps in this imperfect form when it was communicated to the Arabs. Thereafter, the method was probably perfected independently both in Arabia and India. This would account for the difference in the formulation of the rules by the Arabs and by Âryabhaṭa II, the author of the *Mahâsiddhânta*.⁴ It is, however, certain that the Hindus did not borrow the method from the Arabs, because Âryabhaṭa II wrote before Avicenna. Behâ Eddîn⁵ (*c.* 1600) gives the check of nines in exactly the same form as Âryabhaṭa II.