Class 9th Chapter 1st Number System

We have learnt about various types of numbers in our earlier classes let us review them and learn more about numbers

1. Natural Numbers counting numbers are called natural numbers
eg:- N={1, 2,3....}
2.Whole Numbers :- All natural number together with zero are called whole numbers
eg:- {0, 1,2,3.....}
3. Integer :- All natural numbers 0 and negative of natural numbers from the collection of all integers it represented by Z

4:- Rational numbers The number which can be express in the form of p/q is known as rational number( Where q≠0)
eg:-(0, 1,2..) 1/2, 1/3...

Number System

The number system is a collection of numbers used to represent different quantities. There are various types of numbers in the number system:

• Natural Numbers (N): Positive integers like 1, 2, 3, and so on.
• Whole Numbers (W): All natural numbers including 0 (e.g., 0, 1, 2, 3).
• Integers (Z): Whole numbers that can be positive, negative, or zero.
• Rational Numbers (Q): Numbers that can be expressed as the ratio of two integers, where the denominator is not zero (e.g., p/q), \( p \) and \( q \) are integers, \( q ≠0 \)).
• Irrational Numbers: Numbers that cannot be expressed as a simple fraction (e.g.,√2, √3... \), \( \pi \)).
• Real Numbers (R): All rational and irrational numbers.

Each type of number has its own properties and applications in mathematics and everyday life.