A History of the Kerala School of Hindu Astronomy (in Perspective) c8.s5.4

c8.s5.4

‘The three sums of the products of the sides, taken two at a time, are to be multiplied together and divided by the product of the sums of the sides taken three at a time and diminished by the fourth. If a circle is drawn with the square root of this quantity as radius, the whole quadrilateral will be situated inside it.’