Class 9 Maths - Detailed Notes with Formulas

Complete notes with clear explanations, in-depth content, and formulas for every chapter

Chapter 1: Number Systems

Overview: Number systems consist of different types of numbers like Natural numbers, Integers, Rational numbers, Irrational numbers, and Real numbers.

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Chapter 2: Polynomials

Overview: A polynomial is an algebraic expression consisting of variables raised to whole-number powers, and coefficients, combined using addition, subtraction, and multiplication.

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Chapter 3: Coordinate Geometry

Overview: This chapter deals with the coordinate system used to locate points on a plane using two perpendicular axes, called the x-axis and y-axis.

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Chapter 4: Linear Equations in Two Variables

Overview: Linear equations in two variables represent lines on a graph. They are of the form ax + by = c, where a, b, and c are constants.

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Chapter 5: Introduction to Euclid's Geometry

Overview: Euclid's Geometry is a branch of mathematics that deals with the properties, measurement, and relationships of points, lines, angles, and figures in space.

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Chapter 6: Lines and Angles

Overview: This chapter deals with the relationships between different types of angles formed when two lines intersect or when a line cuts through parallel lines.

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Chapter 7: Triangles

Overview: Triangles are a type of polygon with three sides. This chapter focuses on the properties and types of triangles, such as scalene, isosceles, and equilateral triangles.

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Chapter 8: Quadrilaterals

Overview: This chapter covers the properties of quadrilaterals, including parallelograms, rectangles, squares, and rhombuses.

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Chapter 9: Areas of Parallelograms and Triangles

Overview: This chapter deals with the calculation of areas of triangles, parallelograms, and special quadrilaterals using different formulas.

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Chapter 10: Circles

Overview: This chapter explains the properties of circles, including the radius, diameter, circumference, and sector of a circle.

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Chapter 11: Constructions

Overview: This chapter deals with the geometric constructions of various shapes like bisectors of angles and line segments, and constructions of triangles.

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Chapter 12: Heron's Formula

Overview: Heron's formula allows us to calculate the area of a triangle when the lengths of all three sides are known.

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Chapter 13: Surface Areas and Volumes

Overview: This chapter focuses on the surface areas and volumes of different 3D objects like cuboids, cylinders, cones, and spheres.

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Chapter 14: Statistics

Overview: This chapter deals with the collection, analysis, and interpretation of data using various statistical methods.

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Chapter 15: Probability

Overview: This chapter focuses on the concept of probability, which deals with the likelihood of an event happening.

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