Brahmagupta's composition identity (bhavana)
Identidad de Brahmagupta (bhavana)
- Date
- 628 · confidence high
- Place
- Bhinmal, Jalore, Rajasthan, India
- Credited to
- Brahmagupta
- People
- 👤 Brahmagupta598–670
- Field
- Knowledge & symbols
What was discovered
Composition rule that, from two solutions of Nx² + k = y², produces a third; it allows infinitely many solutions of Pell's equation to be generated. It is the first general advance on this equation.
In Europe, Fermat posed the problem in 1657 and Lagrange gave the complete theory in 1768; the name 'Pell's equation' is an error by Euler.
What it led to
- solving indeterminate quadratic equations
- cyclic method of Jayadeva and Bhaskara II