- The first chapter in the Class 9 Maths curriculum typically covers the basics of Number Systems.
- It introduces students to different types of numbers such as natural numbers, whole numbers, integers, rational numbers, and irrational numbers.
- The chapter also explains the properties of these numbers and how they are related to each other.
- Students learn about the representation of numbers on a number line and how to perform operations like addition, subtraction, multiplication, and division with different types of numbers.
- The chapter sets the foundation for understanding more advanced concepts in mathematics.

- A mind map for Chapter One in Class 9 Maths can help students visualize the key concepts and relationships between different topics. Here is a basic structure for the mind map:

Number Systems
- Natural Numbers
- Whole Numbers
- Integers
- Rational Numbers
- Properties
- Representation on a Number Line
- Irrational Numbers
- Properties
- Examples
- Operations with Numbers
- Addition
- Subtraction
- Multiplication
- Division
- This mind map can serve as a helpful study tool for students to review and understand the key concepts covered in the first chapter of their Maths textbook.