1. And it's debatable whether it's Diophantus or whether it's Al- Khwārizmī',

2. The mathematical study of Diophantine problems that Diophantus initiated is now called Diophantine analysis.

3. Under the tutelage of Cosmas, John made such rapid progress that, in the enthusiastic language of his biographer, he soon equalled Diophantus in algebra and Euclid in geometry.