Who is Varahamihir ?
Varahamihira is an Ancient Astronomer from India. He was born in Avanti on 505 CE and died on 587 CE. He is pioneer in mathematics and a great astronomer.
Pancha-Siddhantika is the main book of Varahamihira based on mathematical astronomy.
He is also a great mathematician. His work improves trigonometry (relation between sine and cosine), Optics, Arithmetic, binomial coefficient etc. He also worked to improve some of Aryabhatta’s theories.