Chitrabhanu (mathematician)

Chitrabhanu(IAST:Citrabhānu;fl. 16th century) was a mathematician of theKerala schooland a student ofNilakantha Somayaji.He was aNambudiribrahmin from the town of Covvaram near present dayTrissur.He is noted for akaraṇa,a concise astronomical manual, dated to 1530, analgebraictreatise, and a commentary on a poetic text.Nilakanthaand he were both teachers ofShankara Variyar.

Contributions

He gave integer solutions to 21 types of systems of twosimultaneousDiophantineequations in two unknowns.These types are all the possible pairs of equations of the following seven forms:

$\ x+y=a,x-y=b,xy=c,x^{2}+y^{2}=d,x^{2}-y^{2}=e,x^{3}+y^{3}=f,x^{3}-y^{3}=g$

For each case, Chitrabhanu gave an explanation and justification of his rule as well as an example. Some of his explanations are algebraic, while others are geometric.