Sridhara facts for kids
Śrīdhara (also called Śrīdharācārya) was an important Indian mathematician. He lived a long time ago, around the 8th or 9th century. He is famous for writing books about math. Two of his books, Pāṭīgaṇita and Pāṭīgaṇita-sāra, teach about arithmetic and everyday math. He also wrote a book about algebra called Bījagaṇita, but it is now lost.
Contents
Who Was Śrīdhara?
Not much is known about Śrīdhara's personal life. We don't know where he was born or who his parents were. Some experts think he might have come from the Bengal region or from South India. His writings suggest he was likely a Shaivite Hindu, a follower of the god Shiva.
Other mathematicians mentioned Śrīdhara in their own works. For example, Bhāskara II (who lived in the 12th century) talked about him. Also, Śrīdhara seemed to know the work of Brahmagupta (from the 7th century). Because of these mentions, historians believe Śrīdhara lived in the 8th or early 9th century. Sometimes, people confuse him with other scholars named Śrīdhara from that time.
Śrīdhara's Important Books
Śrīdhara wrote several important math books. Two of them are still available today.
Pāṭīgaṇita
This book is also known as Bṛhat-Pāṭi (meaning "Bigger Pāṭi"). It was a very detailed book about practical math. It covered arithmetic and mensuration. Mensuration is about measuring things like sizes, lengths, areas, and volumes. The book was supposed to have 900 verses, but only 251 are left. Many parts of the book are now missing.
Pāṭīgaṇita-sāra
This book is a shorter version of Pāṭīgaṇita. It is also called Triśatikā because it has 300 verses. It talks about many math topics, including:
- Counting numbers
- Natural numbers and zero
- Different types of measurements
- Multiplication and division
- Fractions
- Squares and cubes
- The rule of three (a way to solve problems using ratios)
- How to calculate interest
- Math for joint businesses or partnerships
- Mensuration (measuring sizes and areas)
Bījagaṇita
Śrīdhara also wrote a book about algebra called Bījagaṇita. Sadly, this book is now lost. However, some parts of it were quoted by other mathematicians. This gives us an idea of what was in it. Some historians also think he might have written another math book called Gaṇita-pan̄caviṁśī.
What Did Śrīdhara Discover?
Śrīdhara made several important contributions to mathematics:
- Understanding Zero: He explained how zero works in math. He wrote that if you add zero to any number, the number stays the same. If you subtract zero, the number also stays the same. And if you multiply any number by zero, the answer is always zero.
- Dividing Fractions: He found a simple way to divide fractions. His method was to multiply the first fraction by the "reciprocal" of the second fraction. The reciprocal is when you flip a fraction upside down (for example, the reciprocal of 2/3 is 3/2).
- Solving Quadratic Equations: He came up with a method to solve quadratic equations. These are equations where the highest power of the variable is 2 (like x²). His method is sometimes called Śrīdhara's method or the Hindu method. The famous quadratic formula that many students learn today can be found using his ideas. Because of this, the formula is sometimes called Śrīdharācārya's formula in some places.
