History of Hindu Mathematics: A Source Book v2.c17.s19.25

v2.c17.s19.25

It has been stated above that, if *m*, *n*, *p*, *q* are rational numbers such that m²± n²<p²± q², we must have $a=(p²-q²)-(m²-n²),$ $b=(p²-q²)+(m²-n²),$ $c=m²+n²,$ $h=2mn=2pq.$