History of Hindu Mathematics: A Source Book v2.c17.s15.4

v2.c17.s15.4

**Bhâskara's Lemma.** The Cyclic Method of Bhâskara II is based upon the following Lemma: $If Na²+k=b²,$ where a, b, k are integers, k being positive or negative, then $N((am+b)/k)²+(m²-N)/k=((bm+Na)/k)²,$ where m is an arbitrary whole number.