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class_6
1
Patterns in Mathematics
ncert_books/class_6/Ganita_Prakash/fegp101.pdf
1 1.1 What is Mathematics? Mathematics is, in large part, the search for patterns, and for the explanations as to why those patterns exist. Such patterns indeed exist all around us—in nature, in our homes and schools, and in the motion of the sun, moon, and stars. They occur in everything that we do and see, from sho...
class_6
2
Lines and Angles
ncert_books/class_6/Ganita_Prakash/fegp102.pdf
2 In this chapter, we will explore some of the most basic ideas of geometry including points, lines, rays, line segments and angles. These ideas form the building blocks of ‘plane geometry’, and will help us in understanding more advanced topics in geometry such as the construction and analysis of different shapes. M...
class_6
3
Number Play
ncert_books/class_6/Ganita_Prakash/fegp103.pdf
3 NUMBER PLAY Numbers are used in different contexts and in many different ways to organise our lives. We have used numbers to count, and have applied the basic operations of addition, subtraction, multiplication and division on them, to solve problems related to our daily lives. In this chapter, we will continue this...
class_6
4
Data Handling and Presentation
ncert_books/class_6/Ganita_Prakash/fegp104.pdf
4 If you ask your classmates about their favourite colours, you will get a list of colours. This list is an example of data. Similarly, if you measure the weight of each student in your class, you would get a collection of measures of weight—again data. Any collection of facts, numbers, measures, observations or other...
class_6
5
Prime Time
ncert_books/class_6/Ganita_Prakash/fegp105.pdf
5 PRIME TIME 5.1 Common Multiples and Common Factors Children sit in a circle and play a game of numbers. One of the children starts by saying ‘1’. The second player says ‘2’, and so on. But when it is the turn of 3, 6, 9, … (multiples of 3), the player should say ‘idli’ instead of the number. When it is the turn of ...
class_6
6
Perimeter and Area
ncert_books/class_6/Ganita_Prakash/fegp106.pdf
6 PERIMETER AND AREA 6.1 Perimeter Do you remember what the perimeter of a closed plane figure is? Let us refresh our understanding! The perimeter of any closed plane figure is the distance covered along its boundary when you go around it once. For a polygon, i.e., a closed plane figure made up of line segments, the ...
class_6
7
Fractions
ncert_books/class_6/Ganita_Prakash/fegp107.pdf
7 Recall that when some whole number of things are shared equally among some number of people, fractions tell us how much each share is. Shabnam: Do you remember, if one roti is divided equally Mukta: Each child will get half a roti. Shabnam: The fraction ‘one half’ is written as Mukta: If one roti is equally shar...
class_6
8
Playing with Constructions
ncert_books/class_6/Ganita_Prakash/fegp108.pdf
8 8.1 Artwork Observe the following figures and try drawing them freehand. Playing with Constructions Chapter 8_Playing with Constructions.indd 187 13-08-2024 16:38:44 Reprint 2025-26 Fig. 8.1 Ganita Prakash | Grade 6 Now, arm yourself with a ruler and a compass. Let us explore if we can draw these figures with...
class_6
9
Symmetry
ncert_books/class_6/Ganita_Prakash/fegp109.pdf
9 Look around you—you may find many objects that catch your attention. Some such things are shown below: SYMMETRY Flower Butterfly Chapter 9_Symmetry.indd 217 13-08-2024 17:05:22 There is something beautiful about the pictures above. The flower looks the same from many different angles. What about the butterfly? N...
class_6
10
The Other Side of Zero
ncert_books/class_6/Ganita_Prakash/fegp110.pdf
10 More and more numbers! Recall that the very first numbers we learned about in the study of mathematics were the counting numbers 1, 2, 3, 4, … Then we learned that there are even more numbers! For example, there is the number 0 (zero), representing nothing, which comes before 1. The number 0 has a very important hi...
class_7
1
Large Numbers Around Us
ncert_books/class_7/gegp1dd/gegp101.pdf
1 1.1 A Lakh Varieties! Eshwarappa is a farmer in Chintamani, a town in Karnataka. He visits the market regularly to buy seeds for his rice field. During one such visit he overheard a conversation between Ramanna and Lakshmamma. Ramanna said, “Earlier our country had about a lakh varieties of rice. Farmers used to pr...
class_7
2
Arithmetic Expressions
ncert_books/class_7/gegp1dd/gegp102.pdf
2 2.1 Simple Expressions You may have seen mathematical phrases like 13 + 2, 20 – 4, 12 × 5, and 18 ÷ 3. Such phrases are called arithmetic expressions. Every arithmetic expression has a value which is the number it evaluates to. For example, the value of the expression 13 + 2 is 15. This expression can be read as ‘1...
class_7
3
A Peek Beyond the Point
ncert_books/class_7/gegp1dd/gegp103.pdf
3 3.1 The Need for Smaller Units Sonu’s mother was fixing a toy. She was trying to join two pieces with the help of a screw. Sonu was watching his mother with great curiosity. His mother was unable to join the pieces. Sonu asked why. His mother said that the screw was not of the right size. She brought another screw ...
class_7
4
Expressions using Letter-Numbers
ncert_books/class_7/gegp1dd/gegp104.pdf
4 4.1 The Notion of Letter-Numbers In this chapter we shall look at a concise way of expressing mathematical relations and patterns. We shall see how this helps us in thinking about these relationships and patterns, and in explaining why they may hold true. Example 1: Shabnam is 3 years older than Aftab. When Aftab’...
class_7
5
Parallel and Intersecting Lines
ncert_books/class_7/gegp1dd/gegp105.pdf
5 5.1 Across the Line Take a piece of square paper and fold it in different ways. Now, on the creases formed by the folds, draw lines using a pencil and a scale. You will notice different lines on the paper. Take any pair of lines and observe their relationship with each other. Do they meet? If they do not meet withi...
class_7
6
Number Play
ncert_books/class_7/gegp1dd/gegp106.pdf
6 NUMBER PLAY 6.1 Numbers Tell us Things What do the numbers in the figure below tell us? Remember the children from the Grade 6 textbook of mathematics? Now, they call out numbers using a different rule. What do you think these numbers mean? Chapter-6.indd 127 4/12/2025 11:59:04 AM The children rearrange themsel...
class_7
7
A Tale of Three Intersecting Lines
ncert_books/class_7/gegp1dd/gegp107.pdf
7 A triangle is the most basic closed shape. As we know, it consists of: Observe the symbol used to denote a triangle and how the triangles are named using their vertices. While naming a triangle, the vertices can come in any order. The three sides meeting at the corners give rise to three angles that we call the ang...
class_7
8
Working with Fractions
ncert_books/class_7/gegp1dd/gegp108.pdf
8 8.1 Multiplication of Fractions Aaron walks 3 kilometres in 1 hour. How far can he walk in 5 hours? This is a simple question. We know that to find the distance, we need to find the product of 5 and 3, i.e., we multiply 5 and 3. Distance covered in 1 hour = 3 km. Therefore, Distance covered in 5 hours = 3 + 3 + ...
class_7
9
Geometric Twins
ncert_books/class_7/gegp1dd2/gegp201.pdf
1 1.1 Geometric Twins The symbol on this signboard needs to be recreated on another board. How do we do it? One way is to trace the outline of this symbol on tracing paper to reconstruct the figure. But this is difficult for big symbols. What else can we do? GEOMETRIC TWINS Chapter-1.indd 1 10/9/2025 11:44:10 AM...
class_7
10
operations with integers
ncert_books/class_7/gegp1dd2/gegp202.pdf
OPERATIONS WITH INTEGERS 2 2.1 A Quick Recap of Integers Rakesh’s Puzzle: A Number Game Rakesh gives you a challenge. “I have thought of two numbers”, he says. “Their sum is 25, and their difference is 11.” Can you tell me the two numbers? You don’t need to use any formulas. Just try different pairs of numbers a...
class_7
11
finding common ground
ncert_books/class_7/gegp1dd2/gegp203.pdf
3 3.1 The Greatest of All Sameeksha is building her new house. The main room of the house is 12 ft by 16 ft. She feels that the room would look nice if the floor is covered with square tiles of the same size. She also wants to use as few tiles as possible, and for the length of the tile to be a whole number of feet. ...
class_7
12
another peek beyond the point
ncert_books/class_7/gegp1dd2/gegp204.pdf
4 4.1 A Quick Recap of Decimals Recall that decimals are the natural extension of the Indian place value system to represent decimal fractions ( 1 10, 1 100, 1 1000, and so on) and their sums. For example, 27.53 refers to a quantity that has: • 2 Tens We have already learned how to multiply and divide fractions. In...
class_7
13
connecting the dots...
ncert_books/class_7/gegp1dd2/gegp205.pdf
5 Jemimah’s batting has been very consistent over the past year. We can expect a century from her in tomorrow’s match. 5.1 Of Questions and Statements Your teacher tells you that they are meeting two of their childhood friends this evening. One is 5 feet tall and the other is 6 feet tall. What is your guess as to ea...
class_7
14
constructions and tilings
ncert_books/class_7/gegp1dd2/gegp206.pdf
6 6.1 Geometric Constructions Eyes Do you recall the ‘Eyes’ construction we did in Grade 6? Of course, eyes can be drawn freehand, but we wanted to construct them so that the lower arc and upper arc of each eye look symmetrical. We relied on our spatial estimation to determine the two centres, A and B (see the figu...
class_7
15
finding the unknown
ncert_books/class_7/gegp1dd2/gegp207.pdf
7 7.1 Find the Unknowns Unknown Weights We have a weighing scale that behaves as follows. The numbers represent same units of weight: Find the unknown weights in the following cases: FINDING THE UNKNOWN Chapter-7.indd 164 10/9/2025 3:19:51 PM Fig. 7.1 Fig. 7.2 Fig. 7.3 Discuss the answers with your classmates. ...
class_8
1
A square and a cube
ncert_books/class_8/hegp1dd/hegp101.pdf
1 A SQUARE AND A CUBE Queen Ratnamanjuri had a will written that described her fortune of ratnas (precious stones) and also included a puzzle. Her son Khoisnam and their 99 relatives were invited to the reading of her will. She wanted to leave all of her ratnas to her son, but she knew that if she did so, all their re...
class_8
2
power play
ncert_books/class_8/hegp1dd/hegp102.pdf
2 POWER PLAY 2.1 Experiencing the Power Play ... An Impossible Venture! Take a sheet of paper, as large a sheet as you can find. Fold it once. Fold it again, and again. How many times can you fold it over and over? Estu says “I heard that a sheet of paper can’t be folded more than 7 times”. Roxie replies “What if w...
class_8
3
a story of numbers
ncert_books/class_8/hegp1dd/hegp103.pdf
3 A STORY OF NUMBERS 3.1 Reema’s Curiosity One lazy afternoon, Reema was flipping through an old book when— whoosh!—a piece of paper slipped out and floated to the floor. She picked it up and stared at the strange symbols all over it. “What is this?” she wondered. She ran to her father, holding the paper as if it wer...
class_8
4
quadrilaterals
ncert_books/class_8/hegp1dd/hegp104.pdf
4 QUADRILATERALS In this chapter, we will study some interesting types of four-sided figures and solve problems based on them. Such figures are commonly known as quadrilaterals. The word ‘quadrilateral’ is derived from Latin words — quadri meaning four, and latus referring to sides. Observe the following figures. (i...
class_8
5
number play
ncert_books/class_8/hegp1dd/hegp105.pdf
5 NUMBER PLAY 5.1 Is This a Multiple Of? Sum of Consecutive Numbers Anshu is exploring sums of consecutive numbers. He has written the following— Now, he is wondering— • “Can I write every natural number as a sum of consecutive numbers?” 7 = 3 + 4 10 = 1 + 2 + 3 + 4 12 = 3 + 4 + 5 15 = 7 + 8 = 4 + 5 + 6 = 1 + 2...
class_8
6
we distribute, yet things multiply
ncert_books/class_8/hegp1dd/hegp106.pdf
6 We have seen how algebra makes use of letter symbols to write general statements about patterns and relations in a compact manner. Algebra can also be used to justify or prove claims and conjectures (like the many properties you saw in the previous chapter) and to solve problems of various kinds. Distributivity is a...
class_8
7
propositional reasoning - 1
ncert_books/class_8/hegp1dd/hegp107.pdf
7 7.1 Observing Similarity in Change We are all familiar with digital images. We often change the size and orientation of these images to suit our needs. Observe the set of images below— PROPORTIONAL REASONING-1 Image A Image B Image C Chapter 7.indd 159 10-07-2025 15:14:27 We can see that all the images are of ...
class_8
8
fractions in disguise
ncert_books/class_8/hegp2dd/hegp201.pdf
1 1.1 Fractions as Percentages You might have heard statements like, “Mega Sale — up to 50% off!” or “Hiya scored 83% in her board exams”. Do you know what the symbol ʻ%ʼ means? This symbol is read as per cent. The word ‘per cent’ is derived from the Latin phrase ‘per centum’, meaning ‘by the hundred’ or ‘out of hund...
class_8
9
the baudhayana-pythagoras theorem
ncert_books/class_8/hegp2dd/hegp202.pdf
2 2.1 Doubling a Square In Baudhāyana’s Śulba-Sūtra (c. 800 BCE), Baudhāyana considers the following question: How can one construct a square having double the area of a given square? A first guess might be to simply double the length of each side of the square. Will this new square have double the area of the orig...
class_8
10
proportional reasoning-2
ncert_books/class_8/hegp2dd/hegp203.pdf
3 3.1 Proportionality—A Quick Recap In an earlier chapter, we explored proportional relationships between quantities and we used the ratio notation to represent such relationships. When two or more related quantities change by the same factor, we call that relationship a proportional relationship. For example, idli b...
class_8
11
exploring some geometrics themes
ncert_books/class_8/hegp2dd/hegp204.pdf
4 In this chapter, we will explore two geometric themes. We will study fractals which are self-similar shapes. They exhibit the same or similar pattern over and over again — but at smaller and smaller scales. We will then look at different ways of visualising solids. 4.1 Fractals One of the most beautiful examples o...
class_8
12
tales by dots and lines
ncert_books/class_8/hegp2dd/hegp205.pdf
5 5.1 The Balancing Act Last year, we learnt about the mean and median. Recall that the mean of some data is the sum of all the values divided by the number of values in the data. The median is the middle value when the data is sorted. We shall try to understand the mean and median from a different perspective and se...
class_8
13
algebra play
ncert_books/class_8/hegp2dd/hegp206.pdf
ALGEBRA PLAY 6 6.1 Algebra Play Over the last two years, we have used algebra to model different situations. We have learned how to solve algebraic equations and find the values of unknown letter-numbers. Let’s now have some fun with algebra. We shall investigate tricks and puzzles, and explain why they work using al...
class_8
14
area
ncert_books/class_8/hegp2dd/hegp207.pdf
7 7.1 Rectangle and Squares How many different ways can you divide a square into 4 parts of equal area? One can actually think of infinitely many such ways! Consider a division, such as — and alter each part as follows. AREA 07_Chapter 7.indd 148 20-12-2025 16:59:54 In each part, the area is compressed along one ...
class_9
1
Number Systems
ncert_books/class_9/iemh1dd/iemh101.pdf
NUMBER SYSTEMS 1 NUMBER SYSTEMS 1.1 Introduction In your earlier classes, you have learnt about the number line and how to represent various types of numbers on it (see Fig. 1.1). positive direction. As far as your eyes can see, there are numbers, numbers and numbers! Just imagine you start from zero and go on wal...
class_9
2
Polynomials
ncert_books/class_9/iemh1dd/iemh102.pdf
POLYNOMIALS 25 POLYNOMIALS 2.1 Introduction You have studied algebraic expressions, their addition, subtraction, multiplication and division in earlier classes. You also have studied how to factorise some algebraic expressions. You may recall the algebraic identities : and x 2 – y 2 = (x + y) (x – y) and their u...
class_9
3
Coordinate Geometry
ncert_books/class_9/iemh1dd/iemh103.pdf
COORDINATE GEOMETRY LEWIS CARROLL, The Hunting of the Snark 3.1 Introduction You have already studied how to locate a point on a number line. You also know how to describe the position of a point on the line. There are many other situations, in which to find a point we are required to describe its position with refer...
class_9
4
Linear Equations in Two Variables
ncert_books/class_9/iemh1dd/iemh104.pdf
LINEAR EQUATIONS IN TWO VARIABLES 55 LINEAR EQUATIONS IN TWO VARIABLES 4.1 Introduction In earlier classes, you have studied linear equations in one variable. Can you write down a linear equation in one variable? You may say that x + 1 = 0, x + 2 = 0 and 2 y + 3 = 0 are examples of linear equations in one variable. ...
class_9
5
Introduction to Euclid's Geometry
ncert_books/class_9/iemh1dd/iemh105.pdf
60 MATHEMATICS INTRODUCTION TO EUCLID’S GEOMETRY 5.1 Introduction The word ‘geometry’ comes form the Greek words ‘geo’, meaning the ‘earth’, and ‘metrein’, meaning ‘to measure’. Geometry appears to have originated from the need for measuring land. This branch of mathematics was studied in various forms in every anci...
class_9
6
Lines and Angles
ncert_books/class_9/iemh1dd/iemh106.pdf
LINES AND ANGLES 6.1 Introduction In Chapter 5, you have studied that a minimum of two points are required to draw a line. You have also studied some axioms and, with the help of these axioms, you proved some other statements. In this chapter, you will study the properties of the angles formed when two lines intersec...
class_9
7
Triangles
ncert_books/class_9/iemh1dd/iemh107.pdf
TRIANGLES 7.1 Introduction You have studied about triangles and their various properties in your earlier classes. You know that a closed figure formed by three intersecting lines is called a triangle. (‘Tri’ means ‘three’). A triangle has three sides, three angles and three vertices. For example, in triangle ABC, den...
class_9
8
Quadrilaterals
ncert_books/class_9/iemh1dd/iemh108.pdf
104 MATHEMATICS QUADRILATERALS 8.1 Properties of a Parallelogram You have already studied quadrilaterals and their types in Class VIII. A quadrilateral has four sides, four angles and four vertices. A parallelogram is a quadrilateral in which both pairs of opposite sides are parallel. Let us perform an activity. C...
class_9
9
Circles
ncert_books/class_9/iemh1dd/iemh109.pdf
116 MATHEMATICS CIRCLES 9.1 Angle Subtended by a Chord at a Point You have already studied about circles and its parts in Class VI. Take a line segment PQ and a point R not on the line containing PQ. Join PR and QR (see Fig. 9.1). Then ∠ PRQ is called the angle subtended by the line segment PQ at the point R. What ...
class_9
10
Heron's Formula
ncert_books/class_9/iemh1dd/iemh110.pdf
HERON’S FORMULA 10.1Area of a Triangle — by Heron’s Formula We know that the area of triangle when its height is given, is 1 2 × base × height. Now suppose that we know the lengths of the sides of a scalene triangle and not the height. Can you still find its area? For instance, you have a triangular park whose side...
class_9
11
Surface Areas and Volumes
ncert_books/class_9/iemh1dd/iemh111.pdf
SURFACE AREAS AND VOLUMES 137 SURFACE AREAS AND VOLUMES 11.1 Surface Area of a Right Circular Cone We have already studied the surface areas of cube, cuboid and cylinder. We will now study the surface area of cone. So far, we have been generating solids by stacking up congruent figures. Incidentally, such figures a...
class_9
12
Statistics
ncert_books/class_9/iemh1dd/iemh112.pdf
STATISTICS 151 STATISTICS 12.1 Graphical Representation of Data The representation of data by tables has already been discussed. Now let us turn our attention to another representation of data, i.e., the graphical representation. It is well said that one picture is better than a thousand words. Usually comparisons a...
class_10
1
Real Numbers
ncert_books/class_10/jemh1dd/jemh101.pdf
1.1 Introduction In Class IX, you began your exploration of the world of real numbers and encountered irrational numbers. We continue our discussion on real numbers in this chapter. We begin with very important properties of positive integers in Sections 1.2, namely the Euclid’s division algorithm and the Fundamental ...
class_10
2
Polynomials
ncert_books/class_10/jemh1dd/jemh102.pdf
10 MATHEMATICS 2.1 Introduction In Class IX, you have studied polynomials in one variable and their degrees. Recall that if p(x) is a polynomial in x, the highest power of x in p(x) is called the degree of the polynomial p(x). For example, 4x + 2 is a polynomial in the variable x of degree 1, 2y2 – 3y + 4 is a poly...
class_10
3
Pair of Linear Equations in Two Variables
ncert_books/class_10/jemh1dd/jemh103.pdf
24 MATHEMATICS 3.1 Introduction You must have come across situations like the one given below : and play Hoopla (a game in which you throw a ring on the items kept in a stall, and if the ring covers any object completely, you get it). The number of times she played Hoopla is half the number of rides she had on the G...
class_10
4
Quadratic Equations
ncert_books/class_10/jemh1dd/jemh104.pdf
38 MATHEMATICS 4.1 Introduction In Chapter 2, you have studied different types of polynomials. One type was the quadratic polynomial of the form ax2 + bx + c, a 0. When we equate this polynomial to zero, we get a quadratic equation. Quadratic equations come up when we deal with many real-life situations. For instan...
class_10
5
Arithmetic Progressions
ncert_books/class_10/jemh1dd/jemh105.pdf
5.1 Introduction You must have observed that in nature, many things follow a certain pattern, such as the petals of a sunflower, the holes of a honeycomb, the grains on a maize cob, the spirals on a pineapple and on a pine cone, etc. examples are : ARITHMETIC PROGRESSIONS 49 (i) Reena applied for a job and got sele...
class_10
6
Triangles
ncert_books/class_10/jemh1dd/jemh106.pdf
6.1 Introduction You are familiar with triangles and many of their properties from your earlier classes. In Class IX, you have studied congruence of triangles in detail. Recall that two figures are said to be congruent, if they have the same shape and the same size. In this chapter, we shall study about those figures ...
class_10
7
Coordinate Geometry
ncert_books/class_10/jemh1dd/jemh107.pdf
7.1 Introduction In Class IX, you have studied that to locate the position of a point on a plane, we require a pair of coordinate axes. The distance of a point from the y-axis is called its x-coordinate, or abscissa. The distance of a point from the x-axis is called its y-coordinate, or ordinate. The coordinates of a ...
class_10
8
Introduction to Trigonometry
ncert_books/class_10/jemh1dd/jemh108.pdf
8.1 Introduction You have already studied about triangles, and in particular, right triangles, in your earlier classes. Let us take some examples from our surroundings where right triangles can be imagined to be formed. For instance : INTRODUCTION TO TRIGONOMETRY 113 1. Suppose the students of a school are visiting ...
class_10
9
Some Applications of Trigonometry
ncert_books/class_10/jemh1dd/jemh109.pdf
SOME APPLICATIONS OF TRIGONOMETRY 133 9.1 Heights and Distances In the previous chapter, you have studied about trigonometric ratios. In this chapter, you will be studying about some ways in which trigonometry is used in the life around you. Let us consider Fig. 8.1 of prvious chapter, which is redrawn below in Fig. ...
class_10
10
Circles
ncert_books/class_10/jemh1dd/jemh110.pdf
10.1 Introduction You have studied in Class IX that a circle is a collection of all points in a plane which are at a constant distance (radius) from a fixed point (centre). You have also studied various terms related to a circle like chord, segment, sector, arc etc. Let us now examine the different situations that can...
class_10
11
Areas Related to Circles
ncert_books/class_10/jemh1dd/jemh111.pdf
154 MATHEMATICS 11.1 Areas of Sector and Segment of a Circle You have already come across the terms sector and segment of a circle in your earlier classes. Recall that the portion (or part) of the circular region enclosed by two radii and the corresponding arc is called a sector of the circle and the portion (or part...
class_10
12
Surface Areas and Volumes
ncert_books/class_10/jemh1dd/jemh112.pdf
SURFACE AREAS AND VOLUMES 161 12.1 Introduction From Class IX, you are familiar with some of the solids like cuboid, cone, cylinder, and sphere (see Fig. 12.1). You have also learnt how to find their surface areas and volumes. SURFACE AREAS AND VOLUMES 12 of two or more of the basic solids as shown above. You mus...
class_10
13
Statistics
ncert_books/class_10/jemh1dd/jemh113.pdf
13.1 Introduction In Class IX, you have studied the classification of given data into ungrouped as well as grouped frequency distributions. You have also learnt to represent the data pictorially in the form of various graphs such as bar graphs, histograms (including those of varying widths) and frequency polygons. In ...
class_10
14
Probability
ncert_books/class_10/jemh1dd/jemh114.pdf
202 MATHEMATICS 14.1 Probability — ATheoretical Approach Let us consider the following situation : When we speak of a coin, we assume it to be ‘fair’, that is, it is symmetrical so that there is no reason for it to come down more often on one side than the other. We call this property of the coin as being ‘unbiased’...
class_11
1
Sets
ncert_books/class_11/kemh1dd/kemh101.pdf
1.1 Introduction The concept of set serves as a fundamental part of the present day mathematics. Today this concept is being used in almost every branch of mathematics. Sets are used to define the concepts of relations and functions. The study of geometry, sequences, probability, etc. requires the knowledge of sets. T...
class_11
2
Relations and Functions
ncert_books/class_11/kemh1dd/kemh102.pdf
2.1 Introduction Much of mathematics is about finding a pattern – a recognisable link between quantities that change. In our daily life, we come across many patterns that characterise relations such as brother and sister, father and son, teacher and student. In mathematics also, we come across many relations such as nu...
class_11
3
Trigonometric Functions
ncert_books/class_11/kemh1dd/kemh103.pdf
3.1 Introduction The word ‘trigonometry’ is derived from the Greek words ‘trigon’ and ‘metron’ and it means ‘measuring the sides of a triangle’. The subject was originally developed to solve geometric problems involving triangles. It was studied by sea captains for navigation, surveyor to map out the new lands, by engi...
class_11
4
Complex Numbers and Quadratic Equations
ncert_books/class_11/kemh1dd/kemh104.pdf
76 MATHEMATICS 4.1 Introduction In earlier classes, we have studied linear equations in one and two variables and quadratic equations in one variable. We have seen that the equation x 2 + 1 = 0 has no real solution as x 2 + 1 = 0 gives x 2 = – 1 and square of every real number is non-negative. So, we need to exten...
class_11
5
Linear Inequalities
ncert_books/class_11/kemh1dd/kemh105.pdf
5.1 Introduction In earlier classes, we have studied equations in one variable and two variables and also solved some statement problems by translating them in the form of equations. Now a natural question arises: ‘Is it always possible to translate a statement problem in the form of an equation? For example, the heigh...
class_11
6
Permutations and Combinations
ncert_books/class_11/kemh1dd/kemh106.pdf
6.1 Introduction Suppose you have a suitcase with a number lock. The number lock has 4 wheels each labelled with 10 digits from 0 to 9. The lock can be opened if 4 specific digits are arranged in a particular sequence with no repetition. Some how, you have forgotten this specific sequence of digits. You remember only ...
class_11
7
Binomial Theorem
ncert_books/class_11/kemh1dd/kemh107.pdf
126 MATHEMATICS 7.1 Introduction In earlier classes, we have learnt how to find the squares and cubes of binomials like a + b and a – b. Using them, we could evaluate the numerical values of numbers like (98)2 = (100 – 2)2 , (999)3 = (1000 – 1)3 , etc. However, for higher powers like (98)5 , (101)6 , etc., the calcu...
class_11
8
Sequences and Series
ncert_books/class_11/kemh1dd/kemh108.pdf
8.1 Introduction In mathematics, the word, “sequence” is used in much the same way as it is in ordinary English. When we say that a collection of objects is listed in a sequence, we usually mean that the collection is ordered in such a way that it has an identified first member, second member, third member and so on. ...
class_11
9
Straight Lines
ncert_books/class_11/kemh1dd/kemh109.pdf
9.1 Introduction We are familiar with two-dimensional coordinate geometry from earlier classes. Mainly, it is a combination of algebra and geometry. A systematic study of geometry by the use of algebra was first carried out by celebrated French philosopher and mathematician René Descartes, in his book ‘La Géométry, pu...
class_11
10
Conic Sections
ncert_books/class_11/kemh1dd/kemh110.pdf
176 MATHEMATICS 10.1 Introduction In the preceding Chapter 10, we have studied various forms of the equations of a line. In this Chapter, we shall study about some other curves, viz., circles, ellipses, parabolas and hyperbolas. The names parabola and hyperbola are given by Apollonius. These curves are in fact, known...
class_11
11
Introduction to Three Dimensional Geometry
ncert_books/class_11/kemh1dd/kemh111.pdf
208 MATHEMATICS 11.1 Introduction You may recall that to locate the position of a point in a plane, we need two intersecting mutually perpendicular lines in the plane. These lines are called the coordinate axes and the two numbers are called the coordinates of the point with respect to the axes. In actual life, we do...
class_11
12
Limits and Derivatives
ncert_books/class_11/kemh1dd/kemh112.pdf
12.1 Introduction This chapter is an introduction to Calculus. Calculus is that branch of mathematics which mainly deals with the study of change in the value of a function as the points in the domain change. First, we give an intuitive idea of derivative (without actually defining it). Then we give a naive definition...
class_11
13
Statistics
ncert_books/class_11/kemh1dd/kemh113.pdf
13.1 Introduction We know that statistics deals with data collected for specific purposes. We can make decisions about the data by analysing and interpreting it. In earlier classes, we have studied methods of representing data graphically and in tabular form. This representation reveals certain salient features or char...
class_11
14
Probability
ncert_books/class_11/kemh1dd/kemh114.pdf
14.1 Event We have studied about random experiment and sample space associated with an experiment. The sample space serves as an universal set for all questions concerned with the experiment. Consider the experiment of tossing a coin two times. An associated sample space is S = {HH, HT, TH, TT}. Now suppose that we ar...
class_12
1
Relations and Functions
ncert_books/class_12/lemh1dd/lemh101.pdf
1.1 Introduction Recall that the notion of relations and functions, domain, co-domain and range have been introduced in Class XI along with different types of specific real valued functions and their graphs. The concept of the term ‘relation’ in mathematics has been drawn from the meaning of relation in English languag...
class_12
2
Inverse Trigonometric Functions
ncert_books/class_12/lemh1dd/lemh102.pdf
18 MATHEMATICS 2.1 Introduction In Chapter 1, we have studied that the inverse of a function f, denoted by f –1, exists if f is one-one and onto. There are many functions which are not one-one, onto or both and hence we can not talk of their inverses. In Class XI, we studied that trigonometric functions are not one-o...
class_12
3
Matrices
ncert_books/class_12/lemh1dd/lemh103.pdf
34 MATHEMATICS 3.1 Introduction The knowledge of matrices is necessary in various branches of mathematics. Matrices are one of the most powerful tools in mathematics. This mathematical tool simplifies our work to a great extent when compared with other straight forward methods. The evolution of concept of matrices is...
class_12
4
Determinants
ncert_books/class_12/lemh1dd/lemh104.pdf
76 MATHEMATICS v All Mathematical truths are relative and conditional. — C.P. STEINMETZ v 4.1 Introduction In the previous chapter, we have studied about matrices and algebra of matrices. We have also learnt that a system of algebraic equations can be expressed in the form of matrices. This means, a system of linear ...
class_12
5
Continuity and Differentiability
ncert_books/class_12/lemh1dd/lemh105.pdf
5.1 Introduction This chapter is essentially a continuation of our study of differentiation of functions in Class XI. We had learnt to differentiate certain functions like polynomial functions and trigonometric functions. In this chapter, we introduce the very important concepts of continuity, differentiability and rel...
class_12
6
Application of Derivatives
ncert_books/class_12/lemh1dd/lemh106.pdf
6.1 Introduction In Chapter 5, we have learnt how to find derivative of composite functions, inverse trigonometric functions, implicit functions, exponential functions and logarithmic functions. In this chapter, we will study applications of the derivative in various disciplines, e.g., in engineering, science, social ...
class_12
7
Integrals
ncert_books/class_12/lemh2dd/lemh201.pdf
7.1 Introduction Differential Calculus is centred on the concept of the derivative. The original motivation for the derivative was the problem of defining tangent lines to the graphs of functions and calculating the slope of such lines. Integral Calculus is motivated by the problem of defining and calculating the area...
class_12
8
Application of Integrals
ncert_books/class_12/lemh2dd/lemh202.pdf
292 MATHEMATICS 8.1 Introduction In geometry, we have learnt formulae to calculate areas of various geometrical figures including triangles, rectangles, trapezias and circles. Such formulae are fundamental in the applications of mathematics to many real life problems. The formulae of elementary geometry allow us to ca...
class_12
9
Differential Equations
ncert_books/class_12/lemh2dd/lemh203.pdf
9.1 Introduction In Class XI and in Chapter 5 of the present book, we discussed how to differentiate a given function f with respect to an independent variable, i.e., how to find f ′(x) for a given function f at each x in its domain of definition. Further, in the chapter on Integral Calculus, we discussed how to find ...
class_12
10
Vector Algebra
ncert_books/class_12/lemh2dd/lemh204.pdf
10.1 Introduction In our day to day life, we come across many queries such as – What is your height? How should a football player hit the ball to give a pass to another player of his team? Observe that a possible answer to the first query may be 1.6 meters, a quantity that involves only one value (magnitude) which is ...
class_12
11
Three Dimensional Geometry
ncert_books/class_12/lemh2dd/lemh205.pdf
11.1 Introduction In Class XI, while studying Analytical Geometry in two dimensions, and the introduction to three dimensional geometry, we confined to the Cartesian methods only. In the previous chapter of this book, we have studied some basic concepts of vectors. We will now use vector algebra to three dimensional g...
class_12
12
Linear Programming
ncert_books/class_12/lemh2dd/lemh206.pdf
394 MATHEMATICS 12.1 Introduction In earlier classes, we have discussed systems of linear equations and their applications in day to day problems. In Class XI, we have studied linear inequalities and systems of linear inequalities in two variables and their solutions by graphical method. Many applications in mathemat...
class_12
13
Probability
ncert_books/class_12/lemh2dd/lemh207.pdf
406 MATHEMATICS 13.1 Introduction In earlier Classes, we have studied the probability as a measure of uncertainty of events in a random experiment. We discussed the axiomatic approach formulated by Russian Mathematician, A.N. Kolmogorov (1903-1987) and treated probability as a function of outcomes of the experiment. W...