Mathematics in Ancient and Medieval India c7.6

c7.6

Equations ( *samakaraṇa*, *samīkaraṇa*, *sadṛśīkaraṇa* etc. ) seem to have been classified in the *Sthānāṅgasūtra* ( c. 300 B. C. ) according to the powers of unknown quantity e.g. *yāvat-tāvat* ( simple ), *varga* ( quadratic ), *ghana* ( cubic ), *varga-varga* ( biquadratic ) etc. But such classification was not maintained. Brahmagupta ( 628 A. D. ) gave the following classifications : ( 1 ) *eka-varṇa samīkaraṇa*—equations in one unknown comprising linear and quadratic equations, ( ii ) *aneka-varṇa samīkaraṇa*— equations in many unknowns, ( iii ) *bhāvita* — equations involving products of unknown. This classification received further elaboration at the hands of Pṛthūdakāsvāmī ( 860 A. D. ) and Bhāskara II ( 1150 A. D. ).