Sridhara

This article is about the mathematician. For the Saka ruler, see Sridharavarman.

Śrīdhara, Sridharacharya, or Śrīdharācāryya (c. 870 CE – c. 930 CE) was an Indian mathematician, Sanskrit pandit and philosopher. He was born in Bhuriśreṣṭi (Bhurisriṣṭi or Bhurśuṭ) village in South Rādha at present day Hugli in West Bengal, then undivided Bengal with its Capital at Gaur. His father's name was Baladevācārya or Baladeva Acharya and his mother's name was Acchoka Devi. His father was a Sanskrit pandit .

Notable work

He is known for two main treatises: Pāṭīgaṇitasāra (also called Triśatika (300) because it was written in three hundred ślokas) and Pāṭīgaṇita (Bengali: পাটীগণিত). Triśatika discusses counting of numbers, natural number, zero, measures, multiplication, fraction, division, squares, cubes, rule of three, interest-calculation, joint business or partnership, and mensuration (the main part of geometry concerned with ascertaining sizes, lengths, areas, and volumes).

Three other works have been attributed to him, namely the Bījaganita, Navasatī, and Bṛhatpati.

His notable work includes:

• He gave an exposition on the zero. He wrote, "If zero is added to any number, the sum is the same number; if zero is subtracted from any number, the number remains unchanged; if zero is multiplied by any number, the product is zero".
• In the case of dividing a fraction he has found out the method of multiplying the fraction by the reciprocal of the divisor.
• He wrote on the practical applications of algebra.
• He separated algebra from arithmetic.
• He was one of the first to give an algorithm for solving quadratic equations (although there is no indication that he considered two solutions). The modern-day quadratic formula is called Sridharacharya's Formula or Sridharacharya's Method in some places. The solution to a quadratic equation of the general form ax² + bx + c = 0, a ≠ 0 is given by

$x={\frac {-b\pm {\sqrt {b^{2}-4ac}}}{2a}}$

Bibliography

• O'Connor, John J.; Robertson, Edmund F., "Sridhara", MacTutor History of Mathematics Archive, University of St Andrews
• The Date of Sridharacharya by S. Srikanta Sastri, The Jaina Antiquary (Jan, 1948)