HISTORIANS of mathematics attribute the first use of the cross x as a symbol for multiplication to William Oughtred (“Clavis Mathematicae”, London, 1631). See W. W. R. Ball's “Short Account ...

A main feature of the NCERT math book is the topic-wise exercises. These help students learn maths in a structured manner. The second chapter in the Class 9 NCERT book is Polynomials, and it is ...