Rational Numbers Class 8 Notes Maths | StudyTution

  • A number that can be expressed in the form p q , where p and q are integers and q ¹ 0, is called a rational number.
  • Lowest form of a rational number – A rational number p q is said to be in the lowest form or simplest form if p and q have no common factor other than 1 and q ¹ 0.
  • Addition, subtraction, multiplication and division of rational numbers are done in the same way as we do for fractions.
  • Rational numbers are closed under the operations of addition, subtraction and multiplication.
  • The operations of addition and multiplication for rational numbers are (i) commutative, (ii) associative
  • The rational number 0 is the additive identity for rational numbers.
  • The rational number 1 is the multiplicative identity for rational numbers.
  • The additive inverse of the rational number a b is –a b and vice-versa.
  • The reciprocal or multiplicative inverse of the rational number a b is c d if × =1. a c  b d
  • Distributivity of rational numbers – For all rational numbers a, b and c a (b + c) = ab + ac a (b – c) = ab – ac
  • Rational numbers can be represented on a number line.
  • Between any two given rational numbers there are  infinitely many rational numbers.
  • The idea of mean helps us to find rational numbers between two given rational numbers
Facebook Comments Box