History of Hindu Mathematics: A Source Book v2.c17.s14.139

v2.c17.s14.139

“In the case of 4 as subtractive, the square of the second is increased by three and by unity ; half the product of these sums and that as diminished by unity (are obtained). The latter multiplied by the first sum less unity is the (required) second root; the former multiplied by the product of the (old) roots will be the first root corresponding to the (new) second root.”