The Sanskrit work 'Aryabhatiya' was written by:

The "Aryabhatiya" is a Sanskrit work on mathematics and astronomy written by Aryabhata in 499 CE, when he was 23 years old. Aryabhata was born in 476 CE and is believed to have worked at Kusumapura, near Pataliputra (Patna), during the Gupta period.

About the Aryabhatiya:

It is written in 121 verses, divided into four sections (padas):

• Gitikapada: large units of time and astronomical constants.
• Ganitapada: mathematics, including arithmetic, algebra, geometry and trigonometry.
• Kalakriyapada: the reckoning of time and planetary positions.
• Golapada: the celestial sphere, eclipses and the shape of the Earth.

Key ideas of Aryabhata:

• He gave a very accurate value of pi (π) as 3.1416 (62,832 divided by 20,000).
• He stated that the Earth rotates on its own axis, which explains the apparent daily movement of the stars.
• He explained that solar and lunar eclipses are caused by the shadows of the Earth and the Moon, not by the demons Rahu and Ketu.
• He calculated the length of the year with great accuracy.
• He used a place-value system and worked on sine tables (jya).

Honours:

India's first satellite, launched on 19 April 1975 with Soviet help, was named "Aryabhata".

Other ancient Indian mathematicians and astronomers:

• Varahamihira (6th century): "Pancha Siddhantika" and "Brihat Samhita"; one of the "Navaratnas" associated with Vikramaditya.
• Brahmagupta (7th century): "Brahmasphutasiddhanta"; gave rules for working with zero and negative numbers.
• Bhaskara I (7th century): wrote commentaries on Aryabhata's work.
• Bhaskaracharya (Bhaskara II, 12th century): "Siddhanta Shiromani", including "Lilavati" (arithmetic) and "Bijaganita" (algebra).
• Baudhayana: "Sulba Sutras", which include an early form of the Pythagorean theorem.

Why not the other options?

• ✗Varahamihira wrote "Brihat Samhita".
• ✗Brahmagupta wrote "Brahmasphutasiddhanta".
• ✗Bhaskaracharya wrote "Lilavati" and "Siddhanta Shiromani".