Lesson Plan Math Class 12 (Ch-1) Relation & Functions
E-LESSON PLAN MATHEMATICS
CLASS-XII
CHAPTER-1 RELATIONS & FUNCTIONS
Rmb dav centnary public school Nawanshahr | |||||
NAME OF THE TEACHER | DINESH KUMAR | ||||
CLASS | 10+2 | CHAPTER | 01 | SUBJECT | MATHEMATICS |
TOPIC | RELATIONS & FUNCTIONS | DURATION : 15 Class Meetings | |||
PRE- REQUISITE KNOWLEDGE:-
Knowledge of set theory chapter 1 class 10+1
Knowledge of Relations and Functions chapter 2 class 10+1
TEACHING AIDS:-
Green Board, Chalk, Duster, Charts, smart board, projector, laptop etc.
METHODOLOGY:-
Lecture cum demonstration and Learning by doing method
LEARNING OBJECTIVES
To explain the
- Cartesian product and different types of relations.
- Reflexive, symmetric, transitive and equivalence relations.
- Different types of functions their domain and range.
- One-one(injective) functions, onto (surjective)functions, bijective functions.
- Composite functions.
- Invertible and inverse of functions.
After studying this lesson students should know the
- concept Cartesian product,
- different types of relations,
- domain and range of relations,
- different types of functions their domain and range,
- bijection of functions and inverse of functions
- composition of functions.
- NCERT Text Book,
- NCERT Exemplar Book of mathematics,
- Resource Material : Worksheets , E-content, Basics and formulas from cbsemathematics.com)
KEY WORDS
Cartesian Product, Domain, Range, Reflexivity, Symmetry , Transitivity, One-One, Onto, Injective, Surjective , Bijective, composition
CONTENT OF THE TOPIC
1) Cartesian Product of two sets
2) Relation, Domain, Range and Co-domain of relation.
3) Different types of relations :- Reflexive, symmetric, transitive and
equivalence relation.
4) Functions, Different types of functions like :- one-one, onto, many
one and bijective functions.
5) Composite functions and Invertible functions.
6) Properties of Inverse Functions.
LEARNING ACTIVITIES:Start the session with little description of the set theory, definition of Cartesian product relations and functions, their domain, co-domain and range.
Set :- A well defined collection of objects is called a set.
If A and B are two non-empty sets, then the Cartesian product A x B is defined as the set of all the ordered pairs of the elements from A to B such that
If A and B are two non-empty sets, then relation R from A to B is a subset of the Cartesian product A x B. This means that number of subsets is equal to the number of relations.
The set of all the first elements of the ordered pairs in a relation R from a set A to a set B is called the domain of the relation R.
The set of all second elements in a relation R from a set A to a set B is called the range of the relation R.
The whole set B is called the co-domain of the relation R.
A relation f from a set A to a set B is said to be a function if every element of set A has one and only one image in set B.
Different types of relations:
If (a, a) ϵ R(relation) ∀ a ϵ A, then the relation is called a reflexive relation.
If (a, b) ϵ R ⇒ (b, a) ϵ R, ∀ a ϵ A, then the relation is called a symmetric relation.
If (a, b) ϵ R and (b, c) ϵ R, ⇒ (a, c) ϵ R, ∀ a ϵ A, then the relation is called transitive relation.
A relation which is reflexive, symmetric and transitive is called an equivalence relation.
Definitions of one-one, onto, many one and bijective functions and their arrow diagrams.
A function f from A to B is said to be one-one function or an injection if different elements of A have different images in B i.e. f(a) = f(b) ⇒ a = b for all a, b ϵ A
A function f from A to B is said to be many one function if two or more elements of set A have the same image in B.
Onto Function(Surjection) :
A function f from A to B is said to be onto function if every element of B is the image of some element in A or
If range of f = co-domain of f then function is called onto function.
A function which is one one and onto is called bijective function.
Explain the Method of finding the domain and range of different functions.
Definition of Composite functions:
Let f: A→B and g:B→C be two functions. Then the function gof: A→C defined by gof(x) =g(f(x)), for all x ∊ A
Composition is possible only if co-domain of first function is = domain of second function.
Now explain the method of finding fog and gof and related problems with the inverse of these functions.
Note:
The composition of function is not commutative i.e. fog ≠ gof
Composition of bijection is also a bijection.
Invertible function:
A function which is one one and onto is called an invertible function.
If a function f is invertible then inverse of f (f-1) exists.
Inverse of a function: Let f be a bijective function from A to B then a function g from B to A is called the inverse of f from A to B.
If f:A→B be a bijective function. Then a function g: B → A is called the inverse of f and is denoted by f-1
Algorithm
i) Obtain the function and check its bijectivity.
ii) If f is bijection then it is invertible.
iii) Put f(x) = y where x ϵ A and y ϵ B
iv) Solve f(x) = y to obtain x in terms of y
v) Replace x by f-1(y)
Properties of inverse of a function:
i) Inverse of a function is unique.
ii) Inverse of a bijection is also bijection.
iii) Inverse of composite function is also composite or (gof)-1 = f-1og-1
REFLECTION OF ACTIVITY
Students will be able to know the
1) Cartesian product of two sets
2) Formation of different relations from the cartesian product.
3) Reflexive, Symmetric, Transitive and Equivalence relation.
4) Functions and their domain and range.
5) One-One, Many-One, Onto and Bijective Functions
IMMEDIATE FEEDBACK
After completing the above activities students will be able to
1) Identify different types of relations.
2) Identify different types of relations and their geometrical aspects.
3) Find the domain, range and codomain of different types of functions
CREATION (e.g. MIND-MAP, COLLAGE, GRAPH, MAP etc.)
DIFFERENTIAL LEARNING
For Below Average Students
- Mind/ Concept maps
- Charts , Models and activity
- Simple questions
- Learning situations through watching video, creating collage, completing puzzles, assignment (click here)
- Group Discussion
- Higher Order Thinking Skill questions
SKILLS ENHANCED
Observation skill, analytical skill, critical thinking, team work, constructive approach, interpersonal skill, engagement in learning process etc.
ASSESSMENT TECHNIQUES:-
- Assignment sheet will be given as home work at the end of the topic.
- Separate sheets which will include questions of logical thinking and Higher order thinking skills will be given to the above average students.
- Class Test , Oral Test , worksheet and Assignments. can be made the part of assessment.
- Re-test(s) will be conducted on the basis of the performance of the students in the test.
PLEASE COMMENT BELOW
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Excellent work👍
ReplyDeleteThank you sir
ReplyDeleteExcellent work 👍
ReplyDeleteIt's very nice and useful to every maths teacher..
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